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Sample records for adipose triglyceride lipase

  1. Adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) deficiencies affect expression of lipolytic activities in mouse adipose tissues.

    Science.gov (United States)

    Morak, Maria; Schmidinger, Hannes; Riesenhuber, Gernot; Rechberger, Gerald N; Kollroser, Manfred; Haemmerle, Guenter; Zechner, Rudolf; Kronenberg, Florian; Hermetter, Albin

    2012-12-01

    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.

  2. Efficient phagocytosis requires triacylglycerol hydrolysis by adipose triglyceride lipase.

    Science.gov (United States)

    Chandak, Prakash G; Radovic, Branislav; Aflaki, Elma; Kolb, Dagmar; Buchebner, Marlene; Fröhlich, Eleonore; Magnes, Christoph; Sinner, Frank; Haemmerle, Guenter; Zechner, Rudolf; Tabas, Ira; Levak-Frank, Sanja; Kratky, Dagmar

    2010-06-25

    Macrophage phagocytosis is an essential biological process in host defense and requires large amounts of energy. To date, glucose is believed to represent the prime substrate for ATP production in macrophages. To investigate the relative contribution of free fatty acids (FFAs) in this process, we determined the phagocytosis rates in normal mouse macrophages and macrophages of adipose triglyceride lipase (ATGL)-deficient mice. ATGL was shown to be the rate-limiting enzyme for the hydrolysis of lipid droplet-associated triacylglycerol (TG) in many tissues. Here, we demonstrate that Atgl(-/-) macrophages fail to efficiently hydrolyze cellular TG stores leading to decreased cellular FFA concentrations and concomitant accumulation of lipid droplets, even in the absence of exogenous lipid loading. The reduced availability of FFAs results in decreased cellular ATP concentrations and impaired phagocytosis suggesting that fatty acids must first go through a cycle of esterification and re-hydrolysis before they are available as energy substrate. Exogenously added glucose cannot fully compensate for the phagocytotic defect in Atgl(-/-) macrophages. Hence, phagocytosis was also decreased in vivo when Atgl(-/-) mice were challenged with bacterial particles. These findings imply that phagocytosis in macrophages depends on the availability of FFAs and that ATGL is required for their hydrolytic release from cellular TG stores. This novel mechanism links ATGL-mediated lipolysis to macrophage function in host defense and opens the way to explore possible roles of ATGL in immune response, inflammation, and atherosclerosis.

  3. Adipose triglyceride lipase in human skeletal muscle is upregulated by exercise training

    DEFF Research Database (Denmark)

    Alsted, Thomas J; Schweiger, Martina; Nybo, Lars;

    2009-01-01

    ) is not changed. Recently, adipose triglyceride lipase (ATGL) was identified as a TG-specific lipase in various rodent tissues. To investigate whether human skeletal muscle ATGL protein is regulated by endurance exercise training, 10 healthy young men completed 8 wk of supervised endurance exercise training...

  4. ADIPOSE TRIGLYCERIDE LIPASE REGULATES BASAL LIPOLYSIS AND LIPID DROPLET SIZE IN ADIPOCYTES

    OpenAIRE

    Miyoshi, Hideaki; Perfield, James W.; Obin, Martin S.; Greenberg, Andrew S.

    2008-01-01

    In adipocytes, lipid droplet (LD) size reflects a balance of triglyceride synthesis (lipogenesis) and hydrolysis (lipolysis). Perilipin A (Peri A), is the most abundant phosphoprotein on the surface of adipocyte LDs and has a crucial role in lipid storage and lipolysis. Adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) are the major rate-determining enzymes for lipolysis in adipocytes. Each of these proteins (Peri A, ATGL and HSL) have been demonstrated to regulate lipid s...

  5. Absence of adipose triglyceride lipase protects from hepatic endoplasmic reticulum stress in mice

    OpenAIRE

    Fuchs, Claudia D.; Claudel, Thierry; Kumari, Pooja; Haemmerle, Guenter; Pollheimer, Marion J.; Stojakovic, Tatjana; Scharnagl, Hubert; Halilbasic, Emina; Gumhold, Judith; Silbert, Dagmar; Koefeler, Harald; Trauner, Michael

    2012-01-01

    Nonalcoholic fatty liver disease (NAFLD) is characterized by triglyceride (TG) accumulation and endoplasmic reticulum (ER) stress. Because fatty acids (FAs) may trigger ER stress, we hypothesized that the absence of adipose triglyceride lipase (ATGL/PNPLA2)-the main enzyme for intracellular lipolysis, releasing FAs, and closest homolog to adiponutrin (PNPLA3) recently implicated in the pathogenesis of NAFLD-protects against hepatic ER stress. Wild-type (WT) and ATGL knockout (KO) mice were ch...

  6. Developmental, hormonal, and nutritional regulation of expression of porcine adipose tissue triglyceride lipase (pATGL) gene

    Science.gov (United States)

    Adipose triglyceride lipase (ATGL) is a newly identified lipase. We report for the first time the porcine ATGL sequence and characterize ATGL gene and protein expression in vitro and in vivo. Adult pig tissue expresses ATGL at high levels in the white adipose and muscle tissue relative to other te...

  7. Adipose triglyceride lipase plays a key role in the supply of the working muscle with fatty acids

    DEFF Research Database (Denmark)

    Schoiswohl, Gabriele; Schweiger, Martina; Schreiber, Renate;

    2010-01-01

    Fatty acids (FA) are mobilized from triglyceride (TG) stores during exercise to supply the working muscle with energy. Mice deficient for adipose triglyceride lipase (ATGLko)exhibit defective lipolysis and accumulate TG in adipose tissue and muscle suggesting that ATGL deficiency affects energy...

  8. Adipose Triglyceride Lipase Deficiency Causes Tissue-specific Changes in Insulin Signaling*

    OpenAIRE

    Kienesberger, Petra C.; Lee, Daeho; Pulinilkunnil, Thomas; Brenner, Daniel S.; Cai, Lingzhi; Magnes, Christoph; Koefeler, Harald C.; Streith, Ingo E.; Rechberger, Gerald N.; Haemmerle, Guenter; Flier, Jeffrey S.; Zechner, Rudolf; Kim, Young-Bum; Kershaw, Erin E.

    2009-01-01

    Triacylglycerol accumulation in insulin target tissues is associated with insulin resistance. Paradoxically, mice with global targeted deletion of adipose triglyceride lipase (ATGL), the rate-limiting enzyme in triacylglycerol hydrolysis, display improved glucose tolerance and insulin sensitivity despite triacylglycerol accumulation in multiple tissues. To determine the molecular mechanisms for this phenotype, ATGL-deficient (ATGL−/−) and wild-type mice were injected with saline or insulin (1...

  9. Contribution of adipose triglyceride lipase and hormone-sensitive lipase to lipolysis in hMADS adipocytes.

    Science.gov (United States)

    Bezaire, Véronic; Mairal, Aline; Ribet, Carole; Lefort, Corinne; Girousse, Amandine; Jocken, Johan; Laurencikiene, Jurga; Anesia, Rodica; Rodriguez, Anne-Marie; Ryden, Mikael; Stenson, Britta M; Dani, Christian; Ailhaud, Gérard; Arner, Peter; Langin, Dominique

    2009-07-01

    Lipolysis is the catabolic pathway by which triglycerides are hydrolyzed into fatty acids. Adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) have the capacity to hydrolyze in vitro the first ester bond of triglycerides, but their respective contributions to whole cell lipolysis in human adipocytes is unclear. Here, we have investigated the roles of HSL, ATGL, and its coactivator CGI-58 in basal and forskolin-stimulated lipolysis in a human white adipocyte model, the hMADS cells. The hMADS adipocytes express the various components of fatty acid metabolism and show lipolytic capacity similar to primary cultured adipocytes. We show that lipolysis and fatty acid esterification are tightly coupled except in conditions of stimulated lipolysis. Immunocytochemistry experiments revealed that acute forskolin treatment promotes HSL translocation from the cytosol to small lipid droplets and redistribution of ATGL from the cytosol and large lipid droplets to small lipid droplets, resulting in enriched colocalization of the two lipases. HSL or ATGL overexpression resulted in increased triglyceride-specific hydrolase capacity, but only ATGL overexpression increased whole cell lipolysis. HSL silencing had no effect on basal lipolysis and only partially reduced forskolin-stimulated lipolysis. Conversely, silencing of ATGL or CGI-58 significantly reduced basal lipolysis and essentially abolished forskolin-stimulated lipolysis. Altogether, these results suggest that ATGL/CGI-58 acts independently of HSL and precedes its action in the sequential hydrolysis of triglycerides in human hMADS adipocytes. PMID:19433586

  10. Contribution of Adipose Triglyceride Lipase and Hormone-sensitive Lipase to Lipolysis in hMADS Adipocytes*

    Science.gov (United States)

    Bezaire, Véronic; Mairal, Aline; Ribet, Carole; Lefort, Corinne; Girousse, Amandine; Jocken, Johan; Laurencikiene, Jurga; Anesia, Rodica; Rodriguez, Anne-Marie; Ryden, Mikael; Stenson, Britta M.; Dani, Christian; Ailhaud, Gérard; Arner, Peter; Langin, Dominique

    2009-01-01

    Lipolysis is the catabolic pathway by which triglycerides are hydrolyzed into fatty acids. Adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) have the capacity to hydrolyze in vitro the first ester bond of triglycerides, but their respective contributions to whole cell lipolysis in human adipocytes is unclear. Here, we have investigated the roles of HSL, ATGL, and its coactivator CGI-58 in basal and forskolin-stimulated lipolysis in a human white adipocyte model, the hMADS cells. The hMADS adipocytes express the various components of fatty acid metabolism and show lipolytic capacity similar to primary cultured adipocytes. We show that lipolysis and fatty acid esterification are tightly coupled except in conditions of stimulated lipolysis. Immunocytochemistry experiments revealed that acute forskolin treatment promotes HSL translocation from the cytosol to small lipid droplets and redistribution of ATGL from the cytosol and large lipid droplets to small lipid droplets, resulting in enriched colocalization of the two lipases. HSL or ATGL overexpression resulted in increased triglyceride-specific hydrolase capacity, but only ATGL overexpression increased whole cell lipolysis. HSL silencing had no effect on basal lipolysis and only partially reduced forskolin-stimulated lipolysis. Conversely, silencing of ATGL or CGI-58 significantly reduced basal lipolysis and essentially abolished forskolin-stimulated lipolysis. Altogether, these results suggest that ATGL/CGI-58 acts independently of HSL and precedes its action in the sequential hydrolysis of triglycerides in human hMADS adipocytes. PMID:19433586

  11. G0/G1 switch gene-2 regulates human adipocyte lipolysis by affecting activity and localization of adipose triglyceride lipase

    NARCIS (Netherlands)

    Schweiger, M.; Paar, M.; Eder, C.; Brandis, J.; Moser, E.; Gorkiewisz, G.; Grond, S.; Radner, F.P.W.; Cerk, I.; Cornaciu, I.; Oberer, M.; Kersten, A.H.; Zechner, R.; Zimmermann, M.B.; Lass, A.

    2012-01-01

    The hydrolysis of triglycerides in adipocytes, termed lipolysis, provides free fatty acids as energy fuel. Murine lipolysis largely depends on the activity of adipose triglyceride lipase (ATGL)5, which is regulated by two proteins annotated as comparative gene identification-58 (CGI-58) and G0/G1 sw

  12. Adipose triglyceride lipase regulates lipid metabolism in dairy goat mammary epithelial cells.

    Science.gov (United States)

    Li, Jun; Luo, Jun; Wang, Hui; Shi, Hengbo; Zhu, Jiangjiang; Sun, Yuting; Yu, Kang; Yao, Dawei

    2015-01-01

    Adipose triglyceride lipase (ATGL) catalyzes the initial step in the lipid lipolysis process, hydrolyzing triglyceride (TG) to produce diacylglycerol (DG) and free fatty acids (FFA). In addition, ATGL regulates lipid storage and release in adipocyte cells. However, its role in mammary gland tissue remains unclear. To assess the role of the ATGL gene in the goat mammary gland, this study analyzed the tissue distribution and expression of key genes together with lipid accumulation after knockdown of the ATGL gene. The mRNA of ATGL was highly expressed in subcutaneous adipose tissue, the lung and the mammary gland with a significant increase in expression during the lactation period compared with the dry period of the mammary gland. Knockdown of the ATGL gene in goat mammary epithelial cells (GMECs) using siRNA resulted in a significant decrease in both ATGL mRNA and protein levels. Silencing of the ATGL gene markedly increased lipid droplet accumulation and intracellular TG concentration (Pfat formation and secretion was down-regulated (PCD36 for fatty acid uptake (P<0.05). In conclusion, these data suggest that the ATGL gene plays an important role in triglyceride lipolysis in GMECs and provides the first experimental evidence that ATGL may be involved in lipid metabolism during lactation. PMID:25307872

  13. Loss of adipose triglyceride lipase is associated with human cancer and induces mouse pulmonary neoplasia.

    Science.gov (United States)

    Al-Zoughbi, Wael; Pichler, Martin; Gorkiewicz, Gregor; Guertl-Lackner, Barbara; Haybaeck, Johannes; Jahn, Stephan W; Lackner, Carolin; Liegl-Atzwanger, Bernadette; Popper, Helmut; Schauer, Silvia; Nusshold, Elisa; Kindt, Alida S D; Trajanoski, Zlatko; Speicher, Michael R; Haemmerle, Guenther; Zimmermann, Robert; Zechner, Rudolf; Vesely, Paul W; Hoefler, Gerald

    2016-06-01

    Metabolic reprogramming is a hallmark of cancer. Understanding cancer metabolism is instrumental to devise innovative therapeutic approaches. Anabolic metabolism, including the induction of lipogenic enzymes, is a key feature of proliferating cells. Here, we report a novel tumor suppressive function for adipose triglyceride lipase (ATGL), the rate limiting enzyme in the triglyceride hydrolysis cascade.In immunohistochemical analysis, non-small cell lung cancers, pancreatic adenocarcinoma as well as leiomyosarcoma showed significantly reduced levels of ATGL protein compared to corresponding normal tissues. The ATGL gene was frequently deleted in various forms of cancers. Low levels of ATGL mRNA correlated with significantly reduced survival in patients with ovarian, breast, gastric and non-small cell lung cancers. Remarkably, pulmonary neoplasia including invasive adenocarcinoma developed spontaneously in mice lacking ATGL pointing to an important role for this lipase in controlling tumor development.Loss of ATGL, as detected in several forms of human cancer, induces spontaneous development of pulmonary neoplasia in a mouse model. Our results, therefore, suggest a novel tumor suppressor function for ATGL and contribute to the understanding of cancer metabolism. We propose to evaluate loss of ATGL protein expression for the diagnosis of malignant tumors. Finally, modulation of the lipolytic pathway may represent a novel therapeutic approach in the treatment of human cancer.

  14. Comparative studies of the role of hormone-sensitive lipase and adipose triglyceride lipase in human fat cell lipolysis.

    Science.gov (United States)

    Rydén, Mikael; Jocken, Johan; van Harmelen, Vanessa; Dicker, Andrea; Hoffstedt, Johan; Wirén, Mikael; Blomqvist, Lennart; Mairal, Aline; Langin, Dominique; Blaak, Ellen; Arner, Peter

    2007-06-01

    Hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) regulate adipocyte lipolysis in rodents. The purpose of this study was to compare the roles of these lipases for lipolysis in human adipocytes. Subcutaneous adipose tissue was investigated. HSL and ATGL protein expression were related to lipolysis in isolated mature fat cells. ATGL or HSL were knocked down by RNA interference (RNAi) or selectively inhibited, and effects on lipolysis were studied in differentiated preadipocytes or adipocytes derived from human mesenchymal stem cells (hMSC). Subjects were all women. There were 12 lean controls, 8 lean with polycystic ovary syndrome (PCOS), and 27 otherwise healthy obese subjects. We found that norepinephrine-induced lipolysis was positively correlated with HSL protein levels (P < 0.0001) but not with ATGL protein. Women with PCOS or obesity had significantly decreased norepinephrine-induced lipolysis and HSL protein expression but no change in ATGL protein expression. HSL knock down by RNAi reduced basal and catecholamine-induced lipolysis. Knock down of ATGL decreased basal lipolysis but did not change catecholamine-stimulated lipolysis. Treatment of hMSC with a selective HSL inhibitor during and/or after differentiation in adipocytes reduced basal lipolysis by 50%, but stimulated lipolysis was inhibited completely. In contrast to findings in rodents, ATGL is of less importance than HSL in regulating catecholamine-induced lipolysis and cannot replace HSL when this enzyme is continuously inhibited. However, both lipases regulate basal lipolysis in human adipocytes. ATGL expression, unlike HSL, is not influenced by obesity or PCOS. PMID:17327373

  15. New Atglistatin closely related analogues: Synthesis and structure-activity relationship towards adipose triglyceride lipase inhibition.

    Science.gov (United States)

    Roy, Pierre-Philippe; D'Souza, Kenneth; Cuperlovic-Culf, Miroslava; Kienesberger, Petra C; Touaibia, Mohamed

    2016-08-01

    Adipose Triglyceride Lipase (ATGL) performs the first and rate-limiting step in lipolysis by hydrolyzing triacylglycerols stored in lipid droplets to diacylglycerols. By mediating lipolysis in adipose and non-adipose tissues, ATGL is a major regulator of overall energy metabolism and plasma lipid levels. Since chronically high levels of plasma lipids are linked to metabolic disorders including insulin resistance and type 2 diabetes, ATGL is an interesting therapeutic target. In the present study, fourteen closely related analogues of Atglistatin (1), a newly discovered ATGL inhibitor, were synthesized, and their ATGL inhibitory activity was evaluated. The effect of these analogues on lipolysis in 3T3-L1 adipocytes clearly shows that inhibition of the enzyme by Atglistatin (1) is due to the presence of the carbamate and N,N-dimethyl moieties on the biaryl central core at meta and para position, respectively. Mono carbamate-substituted analogue C2, in which the carbamate group was in the meta position as in Atglistatin (1), showed slight inhibition. Low dipole moment of Atglistatin (1) compared to the synthesized analogues possibly explains the lower inhibitory activities. PMID:27155760

  16. New Atglistatin closely related analogues: Synthesis and structure-activity relationship towards adipose triglyceride lipase inhibition.

    Science.gov (United States)

    Roy, Pierre-Philippe; D'Souza, Kenneth; Cuperlovic-Culf, Miroslava; Kienesberger, Petra C; Touaibia, Mohamed

    2016-08-01

    Adipose Triglyceride Lipase (ATGL) performs the first and rate-limiting step in lipolysis by hydrolyzing triacylglycerols stored in lipid droplets to diacylglycerols. By mediating lipolysis in adipose and non-adipose tissues, ATGL is a major regulator of overall energy metabolism and plasma lipid levels. Since chronically high levels of plasma lipids are linked to metabolic disorders including insulin resistance and type 2 diabetes, ATGL is an interesting therapeutic target. In the present study, fourteen closely related analogues of Atglistatin (1), a newly discovered ATGL inhibitor, were synthesized, and their ATGL inhibitory activity was evaluated. The effect of these analogues on lipolysis in 3T3-L1 adipocytes clearly shows that inhibition of the enzyme by Atglistatin (1) is due to the presence of the carbamate and N,N-dimethyl moieties on the biaryl central core at meta and para position, respectively. Mono carbamate-substituted analogue C2, in which the carbamate group was in the meta position as in Atglistatin (1), showed slight inhibition. Low dipole moment of Atglistatin (1) compared to the synthesized analogues possibly explains the lower inhibitory activities.

  17. Adipose triglyceride lipase is a TG hydrolase of the small intestine and regulates intestinal PPARα signaling.

    Science.gov (United States)

    Obrowsky, Sascha; Chandak, Prakash G; Patankar, Jay V; Povoden, Silvia; Schlager, Stefanie; Kershaw, Erin E; Bogner-Strauss, Juliane G; Hoefler, Gerald; Levak-Frank, Sanja; Kratky, Dagmar

    2013-02-01

    Adipose triglyceride lipase (ATGL) is the rate-limiting enzyme mediating triglyceride (TG) hydrolysis. The lack of ATGL results in TG accumulation in multiple tissues, underscoring the critical role of ATGL in maintaining lipid homeostasis. Recent evidence suggests that ATGL affects TG metabolism via activation of peroxisome proliferator-activated receptor α (PPARα). To investigate specific effects of intestinal ATGL on lipid metabolism we generated mice lacking ATGL exclusively in the intestine (ATGLiKO). We found decreased TG hydrolase activity and increased intracellular TG content in ATGLiKO small intestines. Intragastric administration of [(3)H]trioleate resulted in the accumulation of radioactive TG in the intestine, whereas absorption into the systemic circulation was unchanged. Intraperitoneally injected [(3)H]oleate also accumulated within TG in ATGLiKO intestines, indicating that ATGL mobilizes fatty acids from the systemic circulation absorbed by the basolateral side from the blood. Down-regulation of PPARα target genes suggested modulation of cholesterol absorption by intestinal ATGL. Accordingly, ATGL deficiency in the intestine resulted in delayed cholesterol absorption. Importantly, this study provides evidence that ATGL has no impact on intestinal TG absorption but hydrolyzes TGs taken up from the intestinal lumen and systemic circulation. Our data support the role of ATGL in modulating PPARα-dependent processes also in the small intestine.

  18. Micro RNA-124a Regulates Lipolysis via Adipose Triglyceride Lipase and Comparative Gene Identification 58

    Directory of Open Access Journals (Sweden)

    Suman K. Das

    2015-04-01

    Full Text Available Lipolysis is the biochemical pathway responsible for the catabolism of cellular triacylglycerol (TG. Lipolytic TG breakdown is a central metabolic process leading to the generation of free fatty acids (FA and glycerol, thereby regulating lipid, as well as energy homeostasis. The precise tuning of lipolysis is imperative to prevent lipotoxicity, obesity, diabetes and other related metabolic disorders. Here, we present our finding that miR-124a attenuates RNA and protein expression of the major TG hydrolase, adipose triglyceride lipase (ATGL/PNPLA2 and its co-activator comparative gene identification 58 (CGI-58/ABHD5. Ectopic expression of miR-124a in adipocytes leads to reduced lipolysis and increased cellular TG accumulation. This phenotype, however, can be rescued by overexpression of truncated Atgl lacking its 3'UTR, which harbors the identified miR-124a target site. In addition, we observe a strong negative correlation between miR-124a and Atgl expression in various murine tissues. Moreover, miR-124a regulates the expression of Atgl and Cgi-58 in murine white adipose tissue during fasting as well as the expression of Atgl in murine liver, during fasting and re-feeding. Together, these results point to an instrumental role of miR-124a in the regulation of TG catabolism. Therefore, we suggest that miR-124a may be involved in the regulation of several cellular and organismal metabolic parameters, including lipid storage and plasma FA concentration.

  19. Beta(3)-adrenergic signaling acutely down regulates adipose triglyceride lipase in brown adipocytes.

    Science.gov (United States)

    Deiuliis, Jeffrey A; Liu, Li-Fen; Belury, Martha A; Rim, Jong S; Shin, Sangsu; Lee, Kichoon

    2010-06-01

    Mice exposed to cold rely upon brown adipose tissue (BAT)-mediated nonshivering thermogenesis to generate body heat using dietary glucose and lipids from the liver and white adipose tissue. In this report, we investigate how cold exposure affects the PI3 K/Akt signaling cascade and the expression of genes involved in lipid metabolism and trafficking in BAT. Cold exposure at an early time point led to the activation of the PI3 K/Akt, insulin-like signaling cascade followed by a transient decrease in adipose triglyceride lipase (ATGL) gene and protein expression in BAT. To further investigate how cold exposure-induced signaling altered ATGL expression, cultured primary brown adipocytes were treated with the beta(3)-adrenergic receptor (beta(3)AR) agonist CL 316,243 (CL) resulting in activation of PI3 K/Akt, ERK 1/2, and p38 signaling pathways and significantly decreased ATGL protein levels. ATGL protein levels decreased significantly 30 min post CL treatment suggesting protein degradation. Inhibition of PKA signaling by H89 rescued ATGL levels. The effects of PKA signaling on ATGL were shown to be independent of relevant pathways downstream of PKA such as PI3 K/Akt, ERK 1/2, and p38. However, CL treatment in 3T3-L1 adipocytes did not decrease ATGL protein and mRNA expression, suggesting a distinct response in WAT to beta3-adrenergic agonism. Transitory effects, possibly attributed to acute Akt activation during the early recruitment phase, were noted as well as stable changes in gene expression which may be attributed to beta3-adrenergic signaling in BAT.

  20. G0/G1 switch gene-2 regulates human adipocyte lipolysis by affecting activity and localization of adipose triglyceride lipase

    OpenAIRE

    Schweiger, Martina; Paar, Margret; Eder, Christina; Brandis, Janina; Moser, Elena; Gorkiewicz, Gregor; Grond, Susanne; Radner, Franz P. W.; Cerk, Ines; Cornaciu, Irina; Oberer, Monika; Kersten, Sander; Zechner, Rudolf; Zimmermann, Robert; Lass, Achim

    2012-01-01

    The hydrolysis of triglycerides in adipocytes, termed lipolysis, provides free fatty acids as energy fuel. Murine lipolysis largely depends on the activity of adipose triglyceride lipase (ATGL), which is regulated by two proteins annotated as comparative gene identification-58 (CGI-58) and G0/G1 switch gene-2 (G0S2). CGI-58 activates and G0S2 inhibits ATGL activity. In contrast to mice, the functional role of G0S2 in human adipocyte lipolysis is poorly characterized. Here we show that overexp...

  1. Data on hepatic lipolysis, adipose triglyceride lipase, and hormone-sensitive lipase in fasted and non-fasted C57BL/6J female mice

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    Phillip M. Marvyn

    2016-06-01

    Full Text Available Liver homogenates produced from fasted and non-fasted C57BL/6J female mice were assayed for total lipolytic activity measured as hydrolysis of [9,10-3H(N]-triolein into [3H] free fatty acids (FFA. Liver homogenates were also used for immunoblotting to determine levels of the lipolytic enzymes adipose-triglyceride lipase (ATGL and hormone-sensitive lipase (HSL, as well as site specific phosphorylation at the 14-3-3 binding site of ATGL and the serine 565 and serine 660 sites of HSL. Significantly higher triolein hydrolysis activity was observed in fasted liver samples, as well as a significant increase in total ATGL and a significant decrease in HSL phosphorylation at the S565 site.

  2. Application of a sensitive collection heuristic for very large protein families: Evolutionary relationship between adipose triglyceride lipase (ATGL and classic mammalian lipases

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    Berezovsky Igor

    2006-03-01

    Full Text Available Abstract Background Manually finding subtle yet statistically significant links to distantly related homologues becomes practically impossible for very populated protein families due to the sheer number of similarity searches to be invoked and analyzed. The unclear evolutionary relationship between classical mammalian lipases and the recently discovered human adipose triglyceride lipase (ATGL; a patatin family member is an exemplary case for such a problem. Results We describe an unsupervised, sensitive sequence segment collection heuristic suitable for assembling very large protein families. It is based on fan-like expanding, iterative database searches. To prevent inclusion of unrelated hits, additional criteria are introduced: minimal alignment length and overlap with starting sequence segments, finding starting sequences in reciprocal searches, automated filtering for compositional bias and repetitive patterns. This heuristic was implemented as FAMILYSEARCHER in the ANNIE sequence analysis environment and applied to search for protein links between the classical lipase family and the patatin-like group. Conclusion The FAMILYSEARCHER is an efficient tool for tracing distant evolutionary relationships involving large protein families. Although classical lipases and ATGL have no obvious sequence similarity and differ with regard to fold and catalytic mechanism, homology links detected with FAMILYSEARCHER show that they are evolutionarily related. The conserved sequence parts can be narrowed down to an ancestral core module consisting of three β-strands, one α-helix and a turn containing the typical nucleophilic serine. Moreover, this ancestral module also appears in numerous enzymes with various substrate specificities, but that critically rely on nucleophilic attack mechanisms.

  3. AMP-Activated Kinase Regulates Lipid Droplet Localization and Stability of Adipose Triglyceride Lipase in C. elegans Dauer Larvae.

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    Meng Xie

    Full Text Available Animals have developed diverse mechanisms to adapt to their changing environment. Like many organisms the free-living nematode C. elegans can alternate between a reproductive mode or a diapause-like "dauer" stage during larval development to circumvent harsh environmental conditions. The master metabolic regulator AMP-activated protein kinase (AMPK is critical for survival during the dauer stage, where it phosphorylates adipose triglyceride lipase (ATGL-1 at multiple sites to block lipid hydrolysis and ultimately protect the cellular triglyceride-based energy depot from rapid depletion. However, how the AMPK-mediated phosphorylation affects the function of ATGL-1 has not been characterised at the molecular level. Here we show that AMPK phosphorylation leads to the generation of 14-3-3 binding sites on ATGL-1, which are recognized by the C. elegans 14-3-3 protein orthologue PAR-5. Physical interaction of ATGL-1 with PAR-5 results in sequestration of ATGL-1 away from the lipid droplets and eventual proteasome-mediated degradation. In addition, we also show that the major AMPK phosphorylation site on ATGL-1, Ser 303, is required for both modification of its lipid droplet localization and its degradation. Our data provide mechanistic insight as to how AMPK functions to enhance survival through its ability to protect the accumulated triglyceride deposits from rapid hydrolysis to preserve the energy stores during periods of extended environmental duress.

  4. Identification of a novel phosphorylation site in adipose triglyceride lipase as a regulator of lipid droplet localization.

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    Xie, Xitao; Langlais, Paul; Zhang, Xiaodong; Heckmann, Bradlee L; Saarinen, Alicia M; Mandarino, Lawrence J; Liu, Jun

    2014-06-15

    Adipose triglyceride lipase (ATGL), the rate-limiting enzyme for triacylglycerol (TG) hydrolysis, has long been known to be a phosphoprotein. However, the potential phosphorylation events that are involved in the regulation of ATGL function remain incompletely defined. Here, using a combinatorial proteomics approach, we obtained evidence that at least eight different sites of ATGL can be phosphorylated in adipocytes. Among them, Thr³⁷² resides within the hydrophobic region known to mediate lipid droplet (LD) targeting. Although it had no impact on the TG hydrolase activity, substitution of phosphorylation-mimic Asp for Thr³⁷² eliminated LD localization and LD-degrading capacity of ATGL expressed in HeLa cells. In contrast, mutation of Thr³⁷² to Ala gave a protein that bound LDs and functioned the same as the wild-type protein. In nonstimulated adipocytes, the Asp mutation led to decreased LD association and basal lipolytic activity of ATGL, whereas the Ala mutation produced opposite effects. Moreover, the LD translocation of ATGL upon β-adrenergic stimulation was also compromised by the Asp mutation. In accord with these findings, the Ala mutation promoted and the Asp mutation attenuated the capacity of ATGL to mediate lipolysis in adipocytes under both basal and stimulated conditions. Collectively, these studies identified Thr³⁷² as a novel phosphorylation site that may play a critical role in determining subcellular distribution as well as lipolytic action of ATGL.

  5. Identification of a novel phosphorylation site in adipose triglyceride lipase as a regulator of lipid droplet localization.

    Science.gov (United States)

    Xie, Xitao; Langlais, Paul; Zhang, Xiaodong; Heckmann, Bradlee L; Saarinen, Alicia M; Mandarino, Lawrence J; Liu, Jun

    2014-06-15

    Adipose triglyceride lipase (ATGL), the rate-limiting enzyme for triacylglycerol (TG) hydrolysis, has long been known to be a phosphoprotein. However, the potential phosphorylation events that are involved in the regulation of ATGL function remain incompletely defined. Here, using a combinatorial proteomics approach, we obtained evidence that at least eight different sites of ATGL can be phosphorylated in adipocytes. Among them, Thr³⁷² resides within the hydrophobic region known to mediate lipid droplet (LD) targeting. Although it had no impact on the TG hydrolase activity, substitution of phosphorylation-mimic Asp for Thr³⁷² eliminated LD localization and LD-degrading capacity of ATGL expressed in HeLa cells. In contrast, mutation of Thr³⁷² to Ala gave a protein that bound LDs and functioned the same as the wild-type protein. In nonstimulated adipocytes, the Asp mutation led to decreased LD association and basal lipolytic activity of ATGL, whereas the Ala mutation produced opposite effects. Moreover, the LD translocation of ATGL upon β-adrenergic stimulation was also compromised by the Asp mutation. In accord with these findings, the Ala mutation promoted and the Asp mutation attenuated the capacity of ATGL to mediate lipolysis in adipocytes under both basal and stimulated conditions. Collectively, these studies identified Thr³⁷² as a novel phosphorylation site that may play a critical role in determining subcellular distribution as well as lipolytic action of ATGL. PMID:24801391

  6. Genetic mutations in adipose triglyceride lipase and myocardial up-regulation of peroxisome proliferated activated receptor-γ in patients with triglyceride deposit cardiomyovasculopathy

    International Nuclear Information System (INIS)

    Highlights: •Triglyceride deposit cardiomyovasculopathy (TGCV) is a rare severe heart disease. •PPARγ is up-regulated in myocardium in patients with TGCV. •Possible vicious cycle for fatty acid may be involved in pathophysiology of TGCV. -- Abstract: Adipose triglyceride lipase (ATGL, also known as PNPLA2) is an essential molecule for hydrolysis of intracellular triglyceride (TG). Genetic ATGL deficiency is a rare multi-systemic neutral lipid storage disease. Information regarding its clinical profile and pathophysiology, particularly for cardiac involvement, is still very limited. A previous middle-aged ATGL-deficient patient in our institute (Case 1) with severe heart failure required cardiac transplantation (CTx) and exhibited a novel phenotype, “Triglyceride deposit cardiomyovasculopathy (TGCV)”. Here, we tried to elucidate molecular mechanism underlying TGCV. The subjects were two cases with TGCV, including our second case who was a 33-year-old male patient (Case 2) with congestive heart failure requiring CTx. Case 2 was homozygous for a point mutation in the 5′ splice donor site of intron 5 in the ATGL, which results in at least two types of mRNAs due to splicing defects. The myocardium of both patients (Cases 1 and 2) showed up-regulation of peroxisome proliferated activated receptors (PPARs), key transcription factors for metabolism of long chain fatty acids (LCFAs), which was in contrast to these molecules’ lower expression in ATGL-targeted mice. We investigated the intracellular metabolism of LCFAs under human ATGL-deficient conditions using patients’ passaged skin fibroblasts as a model. ATGL-deficient cells showed higher uptake and abnormal intracellular transport of LCFA, resulting in massive TG accumulation. We used these findings from cardiac specimens and cell-biological experiments to construct a hypothetical model to clarify the pathophysiology of the human disorder. In patients with TGCV, even when hydrolysis of intracellular TG

  7. Genetic mutations in adipose triglyceride lipase and myocardial up-regulation of peroxisome proliferated activated receptor-γ in patients with triglyceride deposit cardiomyovasculopathy

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Ken-ichi, E-mail: khirano@cnt-osaka.com [Laboratory of Cardiovascular Disease, Novel, Non-Invasive, and Nutritional Therapeutics (CNT), Graduate School of Medicine, Osaka University, 6-2-3, Furuedai, Suita, Osaka 565-0874 (Japan); Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, 2-2, Yamadaoka, Suita, Osaka 565-0871 (Japan); Tanaka, Tatsuya [Center for Medical Research and Education, Graduate School of Medicine, Osaka University, 2-2, Yamadaoka, Suita, Osaka 565-0871 (Japan); Ikeda, Yoshihiko [Department of Pathology, National Cerebral and Cardiovascular Center, 5-7-1 Fujishirodai, Suita 565-8565 (Japan); Yamaguchi, Satoshi [Laboratory of Cardiovascular Disease, Novel, Non-Invasive, and Nutritional Therapeutics (CNT), Graduate School of Medicine, Osaka University, 6-2-3, Furuedai, Suita, Osaka 565-0874 (Japan); Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, 2-2, Yamadaoka, Suita, Osaka 565-0871 (Japan); Zaima, Nobuhiro [Department of Applied Biochemistry, Kinki University, 3327-204, Nakamachi, Nara 631-8505 (Japan); Kobayashi, Kazuhiro [Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, 7-5-1, Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Suzuki, Akira [Laboratory of Cardiovascular Disease, Novel, Non-Invasive, and Nutritional Therapeutics (CNT), Graduate School of Medicine, Osaka University, 6-2-3, Furuedai, Suita, Osaka 565-0874 (Japan); Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, 2-2, Yamadaoka, Suita, Osaka 565-0871 (Japan); Sakata, Yasuhiko [Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, 2-2, Yamadaoka, Suita, Osaka 565-0871 (Japan); Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, 1-1, Seiryo-cho, Aoba-ku, Sendai 980-8574 (Japan); and others

    2014-01-10

    Highlights: •Triglyceride deposit cardiomyovasculopathy (TGCV) is a rare severe heart disease. •PPARγ is up-regulated in myocardium in patients with TGCV. •Possible vicious cycle for fatty acid may be involved in pathophysiology of TGCV. -- Abstract: Adipose triglyceride lipase (ATGL, also known as PNPLA2) is an essential molecule for hydrolysis of intracellular triglyceride (TG). Genetic ATGL deficiency is a rare multi-systemic neutral lipid storage disease. Information regarding its clinical profile and pathophysiology, particularly for cardiac involvement, is still very limited. A previous middle-aged ATGL-deficient patient in our institute (Case 1) with severe heart failure required cardiac transplantation (CTx) and exhibited a novel phenotype, “Triglyceride deposit cardiomyovasculopathy (TGCV)”. Here, we tried to elucidate molecular mechanism underlying TGCV. The subjects were two cases with TGCV, including our second case who was a 33-year-old male patient (Case 2) with congestive heart failure requiring CTx. Case 2 was homozygous for a point mutation in the 5′ splice donor site of intron 5 in the ATGL, which results in at least two types of mRNAs due to splicing defects. The myocardium of both patients (Cases 1 and 2) showed up-regulation of peroxisome proliferated activated receptors (PPARs), key transcription factors for metabolism of long chain fatty acids (LCFAs), which was in contrast to these molecules’ lower expression in ATGL-targeted mice. We investigated the intracellular metabolism of LCFAs under human ATGL-deficient conditions using patients’ passaged skin fibroblasts as a model. ATGL-deficient cells showed higher uptake and abnormal intracellular transport of LCFA, resulting in massive TG accumulation. We used these findings from cardiac specimens and cell-biological experiments to construct a hypothetical model to clarify the pathophysiology of the human disorder. In patients with TGCV, even when hydrolysis of intracellular TG

  8. Lipase Based Biosensors for Triglyceride Determination

    OpenAIRE

    Rosli Nurul Huwaida; Mohd Zain Zainiharyati; Ahmad Nor Monica

    2016-01-01

    A review of methods development in lipase based biosensor for triglyceride determination was briefly discussed. This review focuses on the basic principle of triglyceride biosensor that includes performances of triglyceride biosensor such as limit of detection, response time, and optimization.

  9. The minimal domain of adipose triglyceride lipase (ATGL ranges until leucine 254 and can be activated and inhibited by CGI-58 and G0S2, respectively.

    Directory of Open Access Journals (Sweden)

    Irina Cornaciu

    Full Text Available Adipose triglyceride lipase (ATGL is the rate-limiting enzyme of lipolysis. ATGL specifically hydrolyzes triacylglycerols (TGs, thereby generating diacylglycerols and free fatty acids. ATGL's enzymatic activity is co-activated by the protein comparative gene identification-58 (CGI-58 and inhibited by the protein G0/G1 switch gene 2 (G0S2. The enzyme is predicted to act through a catalytic dyad (Ser47, Asp166 located within the conserved patatin domain (Ile10-Leu178. Yet, neither an experimentally determined 3D structure nor a model of ATGL is currently available, which would help to understand how CGI-58 and G0S2 modulate ATGL's activity. In this study we determined the minimal active domain of ATGL. This minimal fragment of ATGL could still be activated and inhibited by CGI-58 and G0S2, respectively. Furthermore, we show that this minimal domain is sufficient for protein-protein interaction of ATGL with its regulatory proteins. Based on these data, we generated a 3D homology model for the minimal domain. It strengthens our experimental finding that amino acids between Leu178 and Leu254 are essential for the formation of a stable protein domain related to the patatin fold. Our data provide insights into the structure-function relationship of ATGL and indicate higher structural similarities in the N-terminal halves of mammalian patatin-like phospholipase domain containing proteins, (PNPLA1, -2,- 3 and -5 than originally anticipated.

  10. Adipose TriGlyceride Lipase (ATGL) and Hormone-Sensitive Lipase (HSL) protein expression is decreased in the obese insulin resistant state

    NARCIS (Netherlands)

    Jocken, J.W.; Langin, D.; Smit, E.; Saris, W.H.; Valle, C.; Hul, G.B.J.; Holm, C.; Arner, P.; Blaak, E.E.

    2007-01-01

    Aim/hypothesis: Obesity is associated with increased triacylglycerol (TAG) storage in adipose tissue and insulin resistance. The mobilization of stored TAG is mediated by HSL and the recently discovered ATGL. The aim of the present study was to examine whether ATGL and HSL mRNA and protein expressio

  11. The hepatitis C virus core protein inhibits adipose triglyceride lipase (ATGL)-mediated lipid mobilization and enhances the ATGL interaction with comparative gene identification 58 (CGI-58) and lipid droplets.

    Science.gov (United States)

    Camus, Gregory; Schweiger, Martina; Herker, Eva; Harris, Charles; Kondratowicz, Andrew S; Tsou, Chia-Lin; Farese, Robert V; Herath, Kithsiri; Previs, Stephen F; Roddy, Thomas P; Pinto, Shirly; Zechner, Rudolf; Ott, Melanie

    2014-12-26

    Liver steatosis is a common health problem associated with hepatitis C virus (HCV) and an important risk factor for the development of liver fibrosis and cancer. Steatosis is caused by triglycerides (TG) accumulating in lipid droplets (LDs), cellular organelles composed of neutral lipids surrounded by a monolayer of phospholipids. The HCV nucleocapsid core localizes to the surface of LDs and induces steatosis in cultured cells and mouse livers by decreasing intracellular TG degradation (lipolysis). Here we report that core at the surface of LDs interferes with the activity of adipose triglyceride lipase (ATGL), the key lipolytic enzyme in the first step of TG breakdown. Expressing core in livers or mouse embryonic fibroblasts of ATGL(-/-) mice no longer decreases TG degradation as observed in LDs from wild-type mice, supporting the model that core reduces lipolysis by engaging ATGL. Core must localize at LDs to inhibit lipolysis, as ex vivo TG hydrolysis is impaired in purified LDs coated with core but not when free core is added to LDs. Coimmunoprecipitation experiments revealed that core does not directly interact with the ATGL complex but, unexpectedly, increased the interaction between ATGL and its activator CGI-58 as well as the recruitment of both proteins to LDs. These data link the anti-lipolytic activity of the HCV core protein with altered ATGL binding to CGI-58 and the enhanced association of both proteins with LDs. PMID:25381252

  12. The hepatitis C virus core protein inhibits adipose triglyceride lipase (ATGL)-mediated lipid mobilization and enhances the ATGL interaction with comparative gene identification 58 (CGI-58) and lipid droplets.

    Science.gov (United States)

    Camus, Gregory; Schweiger, Martina; Herker, Eva; Harris, Charles; Kondratowicz, Andrew S; Tsou, Chia-Lin; Farese, Robert V; Herath, Kithsiri; Previs, Stephen F; Roddy, Thomas P; Pinto, Shirly; Zechner, Rudolf; Ott, Melanie

    2014-12-26

    Liver steatosis is a common health problem associated with hepatitis C virus (HCV) and an important risk factor for the development of liver fibrosis and cancer. Steatosis is caused by triglycerides (TG) accumulating in lipid droplets (LDs), cellular organelles composed of neutral lipids surrounded by a monolayer of phospholipids. The HCV nucleocapsid core localizes to the surface of LDs and induces steatosis in cultured cells and mouse livers by decreasing intracellular TG degradation (lipolysis). Here we report that core at the surface of LDs interferes with the activity of adipose triglyceride lipase (ATGL), the key lipolytic enzyme in the first step of TG breakdown. Expressing core in livers or mouse embryonic fibroblasts of ATGL(-/-) mice no longer decreases TG degradation as observed in LDs from wild-type mice, supporting the model that core reduces lipolysis by engaging ATGL. Core must localize at LDs to inhibit lipolysis, as ex vivo TG hydrolysis is impaired in purified LDs coated with core but not when free core is added to LDs. Coimmunoprecipitation experiments revealed that core does not directly interact with the ATGL complex but, unexpectedly, increased the interaction between ATGL and its activator CGI-58 as well as the recruitment of both proteins to LDs. These data link the anti-lipolytic activity of the HCV core protein with altered ATGL binding to CGI-58 and the enhanced association of both proteins with LDs.

  13. Triglyceride selectivity of immobilized Thermomyces lanuginosa lipase in interesterification

    DEFF Research Database (Denmark)

    Rønne, Torben Harald; Pedersen, Lars S.; Xu, Xuebing

    2005-01-01

    The triglyceride (fatty acid) selectivity of an immobilized lipase from Thermomyces lanuginosa (Lipozyme TL IM) was investigated in lipase-catalyzed interesterification reactions between two mono-acid TG in n-hexane. Tristearin (tri-C18:0) was used as a reference in a series of TG with saturated FA...

  14. Structure of the human hepatic triglyceride lipase gene

    International Nuclear Information System (INIS)

    The structure of the human hepatic triglyceride lipase gene was determined from multiple cosmid clones. All the exons, exon-intron junctions, and 845 bp of the 5' and 254 bp of the 3' flanking DNA were sequenced. Comparison of the exon sequences to three previously published cDNA sequences revealed differences in the sequence of the codons for residue 133, 193, 202, and 234 that may represent sequence polymorphisms. By primer extension, hepatic lipase mRNA initiates at an adenine 77 bases upstream of the translation initiation site. The hepatic lipase gene spans over 60 kb containing 9 exons and 8 introns, the latter being all located within the region encoding the mature protein. The exons are all of average size (118-234 bp). Exon 1 encodes the signal peptide, exon 4, a region that binds to the lipoprotein substrate, and exon 5, an evolutionarily highly conserved region of potential catalytic function, and exons 6 and 9 encode sequences rich in basic amino acids thought to be important in anchoring the enzyme to the endothelial surface by interacting with acidic domains of the surface glycosaminoglycans. The human lipoprotein lipase gene has been recently reported to have an identical exon-intron organization containing the analogous structural domains. The observations strongly support the common evolutionary origin of these two lipolytic enzymes

  15. Interaction between the triglyceride lipase ATGL and the arf1 activator GBF1

    KAUST Repository

    Ellong, Emy Njoh

    2011-07-18

    The Arf1 exchange factor GBF1 (Golgi Brefeldin A resistance factor 1) and its effector COPI are required for delivery of ATGL (adipose triglyceride lipase) to lipid droplets (LDs). Using yeast two hybrid, co-immunoprecipitation in mammalian cells and direct protein binding approaches, we report here that GBF1 and ATGL interact directly and in cells, through multiple contact sites on each protein. The C-terminal region of ATGL interacts with N-terminal domains of GBF1, including the catalytic Sec7 domain, but not with full-length GBF1 or its entire N-terminus. The N-terminal lipase domain of ATGL (called the patatin domain) interacts with two C-terminal domains of GBF1, HDS (Homology downstream of Sec7) 1 and HDS2. These two domains of GBF1 localize to lipid droplets when expressed alone in cells, but not to the Golgi, unlike the full-length GBF1 protein, which localizes to both. We suggest that interaction of GBF1 with ATGL may be involved in the membrane trafficking pathway mediated by GBF1, Arf1 and COPI that contributes to the localization of ATGL to lipid droplets.

  16. Lapacho tea (Tabebuia impetiginosa) extract inhibits pancreatic lipase and delays postprandial triglyceride increase in rats.

    Science.gov (United States)

    Kiage-Mokua, Beatrice Nyanchama; Roos, Nils; Schrezenmeir, Jürgen

    2012-12-01

    Earlier work in our laboratory indicated that ethanolic extracts of Tabebuia impetiginosa, Arctium lappa L., Calendula officinalis, Helianthus annuus, Linum usitatissimum and L. propolis, inhibit pancreatic lipase in vitro. In a follow-up study we assessed their effects on plasma triglycerides in rats fed on a fatty meal. Extracts, orlistat or only ethanol were given orally to the rats together with the test meal and the rate of increase of postprandial triglycerides was assessed over 4 h. Clearing of the triglycerides from the blood compartment was abolished by inhibiting lipoprotein lipase with Triton WR-1339. Our results showed that out of all the extracts, the bark of Tabebuia impetiginosa led to a significant delay in the postprandial increase of plasma triglycerides. However, lapachol, which is contained in the bark of Tabebuia impetiginosa and soluble in ethanol, had no lipase inhibitory effect in vitro and hence this substance did not seem to mediate the pertinent effect. PMID:22431070

  17. Monoolein production by triglycerides hydrolysis using immobilized Rhizopus oryzae lipase.

    Science.gov (United States)

    Ghattas, Nesrine; Abidi, Ferid; Galai, Said; Marzouki, M Nejib; Salah, Abderraouf Ben

    2014-07-01

    Lipase extracted from Rhizopus oryzae was immobilized in alginate gel beads. The effects of the immobilization conditions, such as, alginate concentration, CaCl2 concentration and amount of initial enzyme on retained activity (specific activity ratio of entrapped active lipase to free lipase) were investigated. The optimal conditions for lipase entrapment were determined: 2% (w/v) alginate concentration, 100mM CaCl2 and enzyme ratio of 2000IU/mL.In such conditions, immobilized lipase by inclusion in alginate showed a highest stability and activity, on olive oil hydrolysis reaction where it could be reused for 10 cycles. After 15min of hydrolysis reaction, the mass composition of monoolein, diolein and triolein were about 78%, 10% and 12%. Hydrolysis' products purification by column chromatography lead to a successful separation of reaction compounds and provide a pure fraction of monoolein which is considered as the widest used emulsifier in food and pharmaceutical industries. PMID:24755261

  18. Monoolein production by triglycerides hydrolysis using immobilized Rhizopus oryzae lipase.

    Science.gov (United States)

    Ghattas, Nesrine; Abidi, Ferid; Galai, Said; Marzouki, M Nejib; Salah, Abderraouf Ben

    2014-07-01

    Lipase extracted from Rhizopus oryzae was immobilized in alginate gel beads. The effects of the immobilization conditions, such as, alginate concentration, CaCl2 concentration and amount of initial enzyme on retained activity (specific activity ratio of entrapped active lipase to free lipase) were investigated. The optimal conditions for lipase entrapment were determined: 2% (w/v) alginate concentration, 100mM CaCl2 and enzyme ratio of 2000IU/mL.In such conditions, immobilized lipase by inclusion in alginate showed a highest stability and activity, on olive oil hydrolysis reaction where it could be reused for 10 cycles. After 15min of hydrolysis reaction, the mass composition of monoolein, diolein and triolein were about 78%, 10% and 12%. Hydrolysis' products purification by column chromatography lead to a successful separation of reaction compounds and provide a pure fraction of monoolein which is considered as the widest used emulsifier in food and pharmaceutical industries.

  19. Hormone-sensitive lipase, the rate-limiting enzyme in triglyceride hydrolysis, is expressed and active in beta-cells.

    Science.gov (United States)

    Mulder, H; Holst, L S; Svensson, H; Degerman, E; Sundler, F; Ahrén, B; Rorsman, P; Holm, C

    1999-01-01

    Triglycerides in the beta-cell may be important for stimulus-secretion coupling, through provision of a lipid-derived signal, and for pathogenetic events in NIDDM, where lipids may adversely affect beta-cell function. In adipose tissues, hormone-sensitive lipase (HSL) is rate-limiting in triglyceride hydrolysis. Here, we investigated whether this enzyme is also expressed and active in beta-cells. Northern blot analysis and reverse transcription-polymerase chain reaction demonstrated that HSL is expressed in rat islets and in the clonal beta-cell lines INS-1, RINm5F, and HIT-T15. Western blot analysis identified HSL in mouse and rat islets and the clonal beta-cells. In mouse and rat, immunocytochemistry showed a predominant occurrence of HSL in beta-cells, with a presumed cytoplasmic localization. Lipase activity in homogenates of the rodent islets and clonal beta-cells constituted 2.1 +/- 0.6% of that in adipocytes; this activity was immunoinhibited by use of antibodies to HSL. The established HSL expression and activity in beta-cells offer a mechanism whereby lipids are mobilized from intracellular stores. Because HSL in adipocytes is activated by cAMP-dependent protein kinase (PKA), PKA-regulated triglyceride hydrolysis in beta-cells may participate in the regulation of insulin secretion, possibly by providing a lipid-derived signal, e.g., long-chain acyl-CoA and diacylglycerol.

  20. Triglyceride kinetics, tissue lipoprotein lipase, and liver lipogenesis in septic rats

    Energy Technology Data Exchange (ETDEWEB)

    Lanza-Jacoby, S.; Tabares, A. (Jefferson Medical College, Philadelphia, PA (USA))

    1990-04-01

    The mechanism for the development of hypertriglyceridemia during gram-negative sepsis was studied by examining liver production and clearance of very-low-density lipoprotein (VLDL) triglyceride (TG). To assess liver output and peripheral clearance the kinetics of VLDL-TG were determined by a constant iv infusion of (2-3H)glycerol-labeled VLDL. Clearance of VLDL-TG was also evaluated by measuring activities of lipoprotein lipase (LPL) in heart, soleus muscle, and adipose tissue from fasted control, fasted E. coli-treated, fed control, and fed E. coli-treated rats. Lewis inbred rats, 275-300 g, were made septic with 8 x 10(7) live E. coli colonies per 100 g body wt. Twenty-four hours after E. coli injection, serum TG, free fatty acids (FFA), and cholesterol of fasted E. coli-treated rats were elevated by 170, 76, and 16%, respectively. The elevation of serum TG may be attributed to the 67% decrease in clearance rate of VLDL-TG in fasted E. coli-treated rats compared with their fasted controls. The suppressed activities of LPL in adipose tissue, skeletal muscle, and heart were consistent with reduced clearance of TG. Secretion of VLDL-TG declined by 31% in livers of fasted E. coli-treated rats, which was accompanied by a twofold increase in the composition of liver TG. Rates of in vivo TG synthesis in livers of the fasted E. coli-treated rats were twofold higher than in those of fasted control rats. Decreased rate of TG appearance along with the increase in liver synthesis of TG contributed to the elevation of liver lipids in the fasted E. coli-treated rats.

  1. Placental triglyceride accumulation in maternal type 1 diabetes is associated with increased lipase gene expression

    DEFF Research Database (Denmark)

    Lindegaard, Marie Louise Skakkebæk; Damm, Peter; Mathiesen, Elisabeth R;

    2006-01-01

    in placenta is largely unknown. To examine whether maternal type 1 diabetes affects placental lipid metabolism, we measured lipids and mRNA expression of lipase-encoding genes in placentas from women with type 1 diabetes (n = 27) and a control group (n = 21). The placental triglyceride (TG) concentration...... and mRNA expression of endothelial lipase (EL) and hormone-sensitive lipase (HSL) were increased in placentas from women with diabetes. The differences were more pronounced in women with diabetes and suboptimal metabolic control than in women with diabetes and good metabolic control. Placental m...

  2. Combined analysis of six lipoprotein lipase genetic variants on triglycerides, high-density lipoprotein, and ischemic heart disease

    DEFF Research Database (Denmark)

    Wittrup, Hans H; Andersen, Rolf V; Tybjaerg-Hansen, Anne;

    2006-01-01

    Genetic variants in lipoprotein lipase may affect triglycerides, high-density lipoprotein (HDL), and risk of ischemic heart disease (IHD).......Genetic variants in lipoprotein lipase may affect triglycerides, high-density lipoprotein (HDL), and risk of ischemic heart disease (IHD)....

  3. Placental triglyceride accumulation in maternal type 1 diabetes is associated with increased lipase gene expression

    DEFF Research Database (Denmark)

    Lindegaard, Marie Louise Skakkebæk; Damm, Peter; Mathiesen, Elisabeth R;

    2006-01-01

    in placenta is largely unknown. To examine whether maternal type 1 diabetes affects placental lipid metabolism, we measured lipids and mRNA expression of lipase-encoding genes in placentas from women with type 1 diabetes (n = 27) and a control group (n = 21). The placental triglyceride (TG) concentration...

  4. ELMOD2 is anchored to lipid droplets by palmitoylation and regulates adipocyte triglyceride lipase recruitment

    DEFF Research Database (Denmark)

    Suzuki, Michitaka; Murakami, Tatsuro; Cheng, Jinglei;

    2015-01-01

    Adipocyte triglyceride lipase (ATGL) is the major enzyme involved in the hydrolysis of triglycerides. The Arf1-coat protein complex I (COPI) machinery is known to be engaged in the recruitment of ATGL to lipid droplets (LDs), but the regulatory mechanism has not been clarified. In the present study...... cellular triglycerides. These effects of ELMOD2 knockdown were canceled by transfection of small interfering RNA-resistant cDNA of wild-type ELMOD2 but not by that of mutated ELMOD2 lacking the Arf-GAP activity. ELMOD2 was distributed in the endoplasmic reticulum and mitochondria as well as in LDs...

  5. The role of triglyceride lipases in cancer associated cachexia

    OpenAIRE

    Das, Suman K.; Hoefler, Gerald

    2013-01-01

    Cancer associated cachexia (CAC) is a complex multiorgan syndrome frequently associated with various forms of cancer. Affected patients suffer from a dramatic loss of skeletal muscle and adipose tissue. Most cases are accompanied by anorexia, and nutritional supplements are not sufficient to stop or reverse its course. CAC impairs many forms of therapeutic interventions and accounts for 15–20% of all deaths of cancer patients. Recently, several studies have recognized the importance of lipid ...

  6. Use of a fluorescent radiolabeled triacylglycerol as a substrate for lipoprotein lipase and hepatic triglyceride lipase

    International Nuclear Information System (INIS)

    A fluorescent radiolabeled triacylglycerol has been synthesized by using a fluorescent fatty acid (pyrene decanoic acid) and a radiolabeled oleic acid. This analog of the natural substrate, 1(3)pyrene decanoic-2,3 (1,2)-dioleoyl-sn-glycerol, has been tested as substrate for determining lipoprotein lipase and hepatic triacylglycerol lipase activities in post-heparin plasma. Optimal conditions for the determination of the two post-heparin plasma lipases were similar to those using radiolabeled triolein. Using this substrate, both post-heparin lipases exhibited their characteristic properties (pH optimum and effect of inhibitors) and attacked external ester bonds (1 or 3) containing pyrene decanoic and oleic acids at a similar rate

  7. ELMOD2 is anchored to lipid droplets by palmitoylation and regulates adipocyte triglyceride lipase recruitment

    OpenAIRE

    Suzuki, Michitaka; Murakami, Tatsuro; Cheng, Jinglei; Kano, Hiroyuki; Fukata, Masaki; FUJIMOTO, TOYOSHI

    2015-01-01

    Adipocyte triglyceride lipase (ATGL) is the major enzyme involved in the hydrolysis of triglycerides. The Arf1–coat protein complex I (COPI) machinery is known to be engaged in the recruitment of ATGL to lipid droplets (LDs), but the regulatory mechanism has not been clarified. In the present study, we found that ELMOD2, a putative noncanonical Arf–GTPase activating protein (GAP) localizing in LDs, plays an important role in controlling ATGL transport to LDs. We showed that knockdown of ELMOD...

  8. Rare ATGL haplotypes are associated with increased plasma triglyceride concentrations in the Greenland Inuit

    DEFF Research Database (Denmark)

    Johansen, Christopher T; Gallinger, Zane R; Wang, Jian;

    2010-01-01

    To genotype common genetic variants found in the adipose triglyceride lipase (ATGL) gene and test them for association with cardiovascular disease risk factors in the Greenland Inuit.......To genotype common genetic variants found in the adipose triglyceride lipase (ATGL) gene and test them for association with cardiovascular disease risk factors in the Greenland Inuit....

  9. Removal of intra-abdominal visceral adipose tissue improves glucose tolerance in rats: role of hepatic triglyceride storage.

    Science.gov (United States)

    Foster, Michelle T; Shi, Haifei; Seeley, Randy J; Woods, Stephen C

    2011-10-24

    Epidemiological studies have demonstrated a strong link between increased visceral fat and metabolic syndrome. In rodents, removal of intra-abdominal but non-visceral fat improves insulin sensitivity and glucose homeostasis, though previous studies make an imprecise comparison to human physiology because actual visceral fat was not removed. We hypothesize that nutrient release from visceral adipose tissue may have greater consequences on metabolic regulation than nutrient release from non-visceral adipose depots since the latter drains into systemic but not portal circulation. To assess this we surgically decreased visceral white adipose tissue (~0.5 g VWATx) and compared the effects to removal of non-visceral epididymal fat (~4 g; EWATx), combination removal of visceral and non-visceral fat (~4.5 g; EWATx/VWATx) and sham-operated controls, in chow-fed rats. At 8 weeks after surgery, only the groups with visceral fat removed had a significantly improved glucose tolerance, although 8 times more fat was removed in EWATx compared with VWATx. This suggests that mechanisms controlling glucose metabolism are relatively more sensitive to reductions in visceral adipose tissue mass. Groups with visceral fat removed also had significantly decreased hepatic lipoprotein lipase (LPL) and triglyceride content compared with controls, while carnitine palmitoyltransferase (CPT-1A) was decreased in all fat-removal groups. In a preliminary experiment, we assessed the opposite hypothesis; i.e., we transplanted excess visceral fat from a donor rat to the visceral cavity (omentum and mesentery), which drains into the hepatic portal vein, of a recipient rat but observed no major metabolic effect. Overall, our results indicate surgical removal of intra-abdominal fat improves glucose tolerance through mechanism that may be mediated by reductions in liver triglyceride. PMID:21683727

  10. Carboxyl Ester Lipase from Either Mother’s Milk or the Pancreas Is Required for Efficient Dietary Triglyceride Digestion in Suckling Mice1,2

    OpenAIRE

    Miller, Rita; Lowe, Mark E.

    2008-01-01

    Because dietary fats provide an important source of energy in the newborn, the efficient digestion of dietary fats is critical to their well-being. Despite the importance of dietary fat digestion, newborns have a deficiency of pancreatic triglyceride lipase, the predominant digestive lipase in adults. The efficient dietary fat digestion in newborns suggests that other lipases must compensate for the lack of pancreatic triglyceride lipase. In this study, we test the hypothesis that breast milk...

  11. Effects of adipocyte lipoprotein lipase on de novo lipogenesis and white adipose tissue browning.

    Science.gov (United States)

    Bartelt, Alexander; Weigelt, Clara; Cherradi, M Lisa; Niemeier, Andreas; Tödter, Klaus; Heeren, Joerg; Scheja, Ludger

    2013-05-01

    Efficient storage of dietary and endogenous fatty acids is a prerequisite for a healthy adipose tissue function. Lipoprotein lipase (LPL) is the master regulator of fatty acid uptake from triglyceride-rich lipoproteins. In addition to LPL-mediated fatty acid uptake, adipocytes are able to synthesize fatty acids from non-lipid precursor, a process called de novo lipogenesis (DNL). As the physiological relevance of fatty acid uptake versus DNL for brown and white adipocyte function remains unclear, we studied the role of adipocyte LPL using adipocyte-specific LPL knockout animals (aLKO). ALKO mice displayed a profound increase in DNL-fatty acids, especially palmitoleate and myristoleate in brown adipose tissue (BAT) and white adipose tissue (WAT) depots while essential dietary fatty acids were markedly decreased. Consequently, we found increased expression in adipose tissues of genes encoding DNL enzymes (Fasn, Scd1, and Elovl6) as well as the lipogenic transcription factor carbohydrate response element binding protein-β. In a high-fat diet (HFD) study aLKO mice were characterized by reduced adiposity and improved plasma insulin and adipokines. However, neither glucose tolerance nor inflammatory markers were ameliorated in aLKO mice compared to controls. No signs of increased BAT activation or WAT browning were detected in aLKO mice either on HFD or after 1 week of β3-adrenergic stimulation using CL316,243. We conclude that despite a profound increase in DNL-derived fatty acids, proposed to be metabolically favorable, aLKO mice are not protected from metabolic disease per se. In addition, induction of DNL alone is not sufficient to promote browning of WAT. This article is part of a Special Issue entitled Brown and White Fat: From Signaling to Disease.

  12. Medium-Chain Triglyceride Activated Brown Adipose Tissue and Induced Reduction of Fat Mass in C57BL/6J Mice Fed High-fat Diet

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yong; XUE Chang Yong; XU Qing; LIU Ying Hua; ZHANG Xin Sheng; WANG Jin; YU Xiao Ming; ZHANG Rong Xin; XUE Chao; YANG Xue Yan

    2015-01-01

    Objective To investigate activation of brown adipose tissue (BAT) stimulated by medium-chain triglyceride (MCT). Methods 30 Male C57BL/6J obese mice induced by fed high fat diet (HFD) were divided into 2 groups, and fed another HFD with 2% MCT or long-chain triglyceride (LCT) respectively for 12 weeks. Body weight, blood biochemical variables, interscapular brown fat tissue (IBAT) mass, expressions of mRNA and protein of beta 3-adrenergic receptors (β3-AR), uncoupling protein-1 (UCP1), hormone sensitive lipase (HSL), protein kinase A (PKA), and adipose triglyceride lipase (ATGL) in IBAT were measured. Results Significant decrease in body weight and body fat mass was observed in MCT group as compared with LCT group (P<0.05) after 12 weeks. Greater increases in IBAT mass was observed in MCT group than in LCT group (P<0.05). Blood TG, TC, LDL-C in MCT group were decreased significantly, meanwhile blood HDL-C, ratio of HDL-C/LDL-C and norepinephrine were increased markedly. Expressions of mRNA and protein ofβ3-AR, UCP1, PKA, HSL, ATGL in BAT were greater in MCT group than in LCT group (P<0.05). Conclusion Our results suggest that MCT stimulated the activation of BAT, possible via norepinephrine pathway, which might partially contribute to reduction of the body fat mass in obese mice fed high fat diet.

  13. ELMOD2 is anchored to lipid droplets by palmitoylation and regulates adipocyte triglyceride lipase recruitment.

    Science.gov (United States)

    Suzuki, Michitaka; Murakami, Tatsuro; Cheng, Jinglei; Kano, Hiroyuki; Fukata, Masaki; Fujimoto, Toyoshi

    2015-06-15

    Adipocyte triglyceride lipase (ATGL) is the major enzyme involved in the hydrolysis of triglycerides. The Arf1-coat protein complex I (COPI) machinery is known to be engaged in the recruitment of ATGL to lipid droplets (LDs), but the regulatory mechanism has not been clarified. In the present study, we found that ELMOD2, a putative noncanonical Arf-GTPase activating protein (GAP) localizing in LDs, plays an important role in controlling ATGL transport to LDs. We showed that knockdown of ELMOD2 by RNA interference induced an increase in the amount of ATGL existing in LDs and decreased the total cellular triglycerides. These effects of ELMOD2 knockdown were canceled by transfection of small interfering RNA-resistant cDNA of wild-type ELMOD2 but not by that of mutated ELMOD2 lacking the Arf-GAP activity. ELMOD2 was distributed in the endoplasmic reticulum and mitochondria as well as in LDs, but palmitoylation was required only for distribution to LDs. An ELMOD2 mutant deficient in palmitoylation failed to reconstitute the ATGL transport after the ELMOD2 knockdown, indicating that distribution in LDs is indispensable to the functionality of ELMOD2. These results indicate that ELMOD2 regulates ATGL transport and cellular lipid metabolism by modulating the Arf1-COPI activity in LDs.

  14. ELMOD2 is anchored to lipid droplets by palmitoylation and regulates adipocyte triglyceride lipase recruitment.

    Science.gov (United States)

    Suzuki, Michitaka; Murakami, Tatsuro; Cheng, Jinglei; Kano, Hiroyuki; Fukata, Masaki; Fujimoto, Toyoshi

    2015-06-15

    Adipocyte triglyceride lipase (ATGL) is the major enzyme involved in the hydrolysis of triglycerides. The Arf1-coat protein complex I (COPI) machinery is known to be engaged in the recruitment of ATGL to lipid droplets (LDs), but the regulatory mechanism has not been clarified. In the present study, we found that ELMOD2, a putative noncanonical Arf-GTPase activating protein (GAP) localizing in LDs, plays an important role in controlling ATGL transport to LDs. We showed that knockdown of ELMOD2 by RNA interference induced an increase in the amount of ATGL existing in LDs and decreased the total cellular triglycerides. These effects of ELMOD2 knockdown were canceled by transfection of small interfering RNA-resistant cDNA of wild-type ELMOD2 but not by that of mutated ELMOD2 lacking the Arf-GAP activity. ELMOD2 was distributed in the endoplasmic reticulum and mitochondria as well as in LDs, but palmitoylation was required only for distribution to LDs. An ELMOD2 mutant deficient in palmitoylation failed to reconstitute the ATGL transport after the ELMOD2 knockdown, indicating that distribution in LDs is indispensable to the functionality of ELMOD2. These results indicate that ELMOD2 regulates ATGL transport and cellular lipid metabolism by modulating the Arf1-COPI activity in LDs. PMID:25904333

  15. Effects of Rosiglitazone and High Fat Diet on Lipase/Esterase Expression in Adipose Tissue

    OpenAIRE

    Shen, Wen‐Jun; Patel, Shailja; Yu, Zaixin; Jue, Dyron; Kraemer, Fredric B.

    2006-01-01

    A number of intracellular lipase/esterase have been reported in adipose tissue either by functional assays of activity or through proteomic analysis. In the current work, we have studied the relative expression level of 12 members of the lipase/esterase family that are found in white adipose tissue. We found that the relative mRNA levels of ATGL and HSL are the most abundant, being 2–3 fold greater than TGH or ADPN; whereas other intracellular neutral lipase/esterases were expressed at substa...

  16. A micromethod for assay of lipoprotein lipase activity in needle biopsy samples of human adipose tissue and skeletal muscle

    International Nuclear Information System (INIS)

    A rapid and simple procedure for assay of lipoprotein lipase (LPL) activity in small amounts of human adipose tissue and skeletal muscle is described and validated. The enzyme is eluted from tissues with heparin and the activity is determined from the eluate by measuring the release of [14C]oleic acid from a gum arabic stabilized emulsion of glycerol-tri[14C]oleate in a Tris-buffer medium containing albumin and pooled normal human serum. Reproducible results are obtained with amounts of tissue ranging from 2 to 25 mg. The Ksub(m) values of the adipose tissue and skeletal muscle LPL for the triolein substrate were 0.74 +- 0.06 and 0.77 +- 0.05 mmol/l, respectively. The standard radioactive triolein emulsion was hydrolyzed by adipose tissue LPL at a rate closely similar to rat VLDL-triglyceride labeled in vivo with [1-14C]palmitic acid, suggesting that the experimental substrate behaved in a similar manner to the natural substrate. The LPL activity was much higher in adipose tissue than in muscle. In adipose tissue the LPL activity was 2-4 times higher in women than in men whereas no sex difference was present in the LPL activity of muscle. (Auth.)

  17. Modeling the methanolysis of triglyceride catalyzed by immobilized lipase in a continuous-flow packed-bed reactor

    International Nuclear Information System (INIS)

    Highlights: • A Burkholderia lipase was immobilized on alkyl-grafted celite carriers. • Celite-alkyl-lipase catalyzed the methanolysis of triglyceride in packed-bed reactor. • The kinetics of the enzymatic transesterification follows Ping Pong Bi Bi mechanism. • Models were developed to discuss the mass transfer and enzyme kinetics in the PBR. - Abstract: A Burkholderia lipase was immobilized on celite grafted with long alkyl groups. The immobilized lipase-catalyzed methanolysis of sunflower oil in a packed-bed reactor (PBR) follows the Ping Pong Bi Bi mechanism. The external mass transfer and enzymatic reaction that simultaneously occurred in the PBR were investigated via the mathematical models. The overall biodiesel production in the PBR was verified to work in an enzymatic reaction-limited regime. Triglyceride conversion and biodiesel yield were higher under a lower reactant feeding rate, while a larger amount of biocatalyst would be required to achieve the designated conversion rate if a higher reactant feeding rate was employed. The PBR can achieve nearly complete conversion of triglyceride at a biocatalyst bed height of 60 cm (ca. 29 g biocatalyst) and a flow rate of 0.1 ml min−1, whereas the biodiesel yield was lower than 67%, probably due to the positional specificity of Burkholderia lipase and the accumulation of glycerol

  18. Fatty acid composition of adipose tissue triglycerides after weight loss and weight maintenance

    DEFF Research Database (Denmark)

    Kunešová, M; Hlavatý, P; Tvrzická, E;

    2012-01-01

    of the DIOGENES dietary intervention study. After an 8-week low calorie diet (LCD) subjects with > 8 % weight loss were randomized to 5 ad libitum weight maintenance diets for 6 months: low protein (P)/low glycemic index (GI) (LP/LGI), low P/high GI (LP/HGI), high P/low GI (HP/LGI), high P/high GI (HP....../HGI), and a control diet. Fatty acid composition in adipose tissue triglycerides was determined by gas chromatography in 195 subjects before the LCD (baseline), after LCD and weight maintenance. Weight change after the maintenance phase was positively correlated with baseline adipose palmitoleic (16:1n-7...

  19. Hydrolysis characteristics of bovine milk fat and monoacid triglycerides mediated by pregastric lipase from goats and kids.

    Science.gov (United States)

    Lai, D T; MacKenzie, A D; O'Connor, C J; Turner, K W

    1997-10-01

    Commercial extracts from oro-pharyngeal tissues of goats and kids have been used as the source of pregastric lipase and have been processed to yield partially purified samples of the primary pregastric lipase. The activity of these lipases against tributyrylglycerol has been determined over a range of pH and temperatures. Optimum pH conditions for pregastric lipase ranged from pH 5.6 to 6.5 for goats and from pH 5.5 to 6.2 for kids, respectively; the optimum temperature ranged from 43 to 60 degrees C. Optima for kid lipase extended slightly below pH 5.5 and higher than 60 degrees C; which were the limits of the test conditions. The enzymes were also used as catalysts for the hydrolysis of monoacid triglycerides (C4:0 to C12:0) at 40 degrees C and pH 6.5; activity was maximum against tributyrylglycerol (C4:0). Values for the Michaelis-Menten constant, increased as carbon chain length of the carboxylic moiety on the triglycerides increased, but values were identical for pregastric lipases of both goats and kids. Anhydrous milk fat was hydrolyzed by the commercial extracts of pregastric lipases of goats and kids, and the resulting profiles for free fatty acids were very similar to one another and to the corresponding profile for a commercial sample of Parmesan cheese. There appear to be no significant differences in activity between the enzyme preparations from goats and kids.

  20. Angiotensin II Reduces Lipoprotein Lipase Expression in Visceral Adipose Tissue via Phospholipase C β4 Depending on Feeding but Increases Lipoprotein Lipase Expression in Subcutaneous Adipose Tissue via c-Src.

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Uchiyama

    Full Text Available Metabolic syndrome is characterized by visceral adiposity, insulin resistance, high triglyceride (TG- and low high-density lipoprotein cholesterol-levels, hypertension, and diabetes-all of which often cause cardiovascular and cerebrovascular diseases. It remains unclear, however, why visceral adiposity but not subcutaneous adiposity causes insulin resistance and other pathological situations. Lipoprotein lipase (LPL catalyzes hydrolysis of TG in plasma lipoproteins. In the present study, we investigated whether the effects of angiotensin II (AngII on TG metabolism are mediated through an effect on LPL expression. Adipose tissues were divided into visceral adipose tissue (VAT and subcutaneous adipose tissue (SAT for comparison. AngII accelerated LPL expression in SAT but, on the contrary, suppressed its expression in VAT. In both SAT and VAT, AngII signaled through the same type 1 receptor. In SAT, AngII increased LPL expression via c-Src and p38 MAPK signaling. In VAT, however, AngII reduced LPL expression via the Gq class of G proteins and the subsequent phospholipase C β4 (PLCβ4, protein kinase C β1, nuclear factor κB, and inducible nitric oxide synthase signaling pathways. PLCβ4 small interfering RNA experiments showed that PLCβ4 expression is important for the AngII-induced LPL reduction in VAT, in which PLCβ4 expression increases in the evening and falls at night. Interestingly, PLCβ4 expression in VAT decreased with fasting, while AngII did not decrease LPL expression in VAT in a fasting state. In conclusion, AngII reduces LPL expression through PLCβ4, the expression of which is regulated by feeding in VAT, whereas AngII increases LPL expression in SAT. The different effects of AngII on LPL expression and, hence, TG metabolism in VAT and SAT may partly explain their different contributions to the development of metabolic syndrome.

  1. Angiotensin II Reduces Lipoprotein Lipase Expression in Visceral Adipose Tissue via Phospholipase C β4 Depending on Feeding but Increases Lipoprotein Lipase Expression in Subcutaneous Adipose Tissue via c-Src.

    Science.gov (United States)

    Uchiyama, Tsuyoshi; Tomono, Shoichi; Sato, Koichi; Nakamura, Tetsuya; Kurabayashi, Masahiko; Okajima, Fumikazu

    2015-01-01

    Metabolic syndrome is characterized by visceral adiposity, insulin resistance, high triglyceride (TG)- and low high-density lipoprotein cholesterol-levels, hypertension, and diabetes-all of which often cause cardiovascular and cerebrovascular diseases. It remains unclear, however, why visceral adiposity but not subcutaneous adiposity causes insulin resistance and other pathological situations. Lipoprotein lipase (LPL) catalyzes hydrolysis of TG in plasma lipoproteins. In the present study, we investigated whether the effects of angiotensin II (AngII) on TG metabolism are mediated through an effect on LPL expression. Adipose tissues were divided into visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) for comparison. AngII accelerated LPL expression in SAT but, on the contrary, suppressed its expression in VAT. In both SAT and VAT, AngII signaled through the same type 1 receptor. In SAT, AngII increased LPL expression via c-Src and p38 MAPK signaling. In VAT, however, AngII reduced LPL expression via the Gq class of G proteins and the subsequent phospholipase C β4 (PLCβ4), protein kinase C β1, nuclear factor κB, and inducible nitric oxide synthase signaling pathways. PLCβ4 small interfering RNA experiments showed that PLCβ4 expression is important for the AngII-induced LPL reduction in VAT, in which PLCβ4 expression increases in the evening and falls at night. Interestingly, PLCβ4 expression in VAT decreased with fasting, while AngII did not decrease LPL expression in VAT in a fasting state. In conclusion, AngII reduces LPL expression through PLCβ4, the expression of which is regulated by feeding in VAT, whereas AngII increases LPL expression in SAT. The different effects of AngII on LPL expression and, hence, TG metabolism in VAT and SAT may partly explain their different contributions to the development of metabolic syndrome. PMID:26447765

  2. Production of lipase from Pseudomonas gessardii using blood tissue lipid and thereof for the hydrolysis of blood cholesterol and triglycerides and lysis of red blood cells.

    Science.gov (United States)

    Ramani, K; Sekaran, G

    2012-08-01

    The study demonstrates the production of lipase (LIP) from Pseudomonas gessardii using blood tissue lipid as the substrate for the hydrolysis of blood cholesterol and triglycerides. The lipase was purified with the specific activity of 828 U/mg protein and the molecular weight of 56 kDa. The maximum lipase activity was observed at the pH 7.0 and the temperature 37 °C. The amino acid composition of purified lipase was determined by HPLC. The mesoporous activated carbon (MAC) was used for the immobilization of lipase for the repeated use of the enzyme catalyst. The K (m) value of immobilized lipase (MAC-LIP) and the free lipase (LIP) was 0.182 and 1.96 mM, respectively. The V (max) value of MAC-LIP and LIP was 1.33 and 1.26 mM/min, respectively. The MAC and MAC-LIP were characterized by scanning electron microscopy (SEM). The hydrolysis study showed 78 and 100% hydrolysis of triglycerides and cholesterol, respectively, for LIP and 84 and 100% hydrolysis of triglycerides and cholesterol, respectively, for MAC-LIP at the reaction time of 1 h. The effect of lipase on cell wall lysis was carried out on the RBCs of blood plasma. Interestingly, 99.9% lysis of RBCs was observed within 2 h. SEM images and phase contrast microscopy confirmed the lysis of RBCs. This work provides a potential biocatalyst for the hydrolysis of blood cholesterol and triglycerides.

  3. Emulsifying triglycerides with dairy phospholipids instead of soy lecithin modulates gut lipase activity

    DEFF Research Database (Denmark)

    Mathiassen, Jakob Hovalt; Nejrup, Rikke Guldhammer; Frøkiær, Hanne;

    2015-01-01

    in particular to limit fatty acid absorption in babies given infant formulas. Since interaction between the lipid droplet and the gastric and duodenal lipases occur through the hydrophobic/hydrophilic interface, the composition of the emulsifier may be crucial for efficient hydrolysis. We therefore determined...... activity was substantially higher on MPL-emulsified particles, while SL emulsification caused a higher rate of pancreatic lipase hydrolysis, on particles that had not been pre-treated with gastric lipase. MPL emulsification did however cause higher pancreatic lipase activity, when the particles had been...... pre-treated with gastric lipase. The attenuating effect of MPL-emulsification on pancreas lipase activity was validated in vivo in mice. Practical application: Our results show that the activity of gastric lipase, a key enzyme in lipid absorption in neonates, is highly dependent on the phospholipid...

  4. Adipose Co-expression networks across Finns and Mexicans identify novel triglyceride-associated genes

    Directory of Open Access Journals (Sweden)

    Haas Blake E

    2012-12-01

    Full Text Available Abstract Background High serum triglyceride (TG levels is an established risk factor for coronary heart disease (CHD. Fat is stored in the form of TGs in human adipose tissue. We hypothesized that gene co-expression networks in human adipose tissue may be correlated with serum TG levels and help reveal novel genes involved in TG regulation. Methods Gene co-expression networks were constructed from two Finnish and one Mexican study sample using the blockwiseModules R function in Weighted Gene Co-expression Network Analysis (WGCNA. Overlap between TG-associated networks from each of the three study samples were calculated using a Fisher’s Exact test. Gene ontology was used to determine known pathways enriched in each TG-associated network. Results We measured gene expression in adipose samples from two Finnish and one Mexican study sample. In each study sample, we observed a gene co-expression network that was significantly associated with serum TG levels. The TG modules observed in Finns and Mexicans significantly overlapped and shared 34 genes. Seven of the 34 genes (ARHGAP30, CCR1, CXCL16, FERMT3, HCST, RNASET2, SELPG were identified as the key hub genes of all three TG modules. Furthermore, two of the 34 genes (ARHGAP9, LST1 reside in previous TG GWAS regions, suggesting them as the regional candidates underlying the GWAS signals. Conclusions This study presents a novel adipose gene co-expression network with 34 genes significantly correlated with serum TG across populations.

  5. Highly efficient extraction and lipase-catalyzed transesterification of triglycerides from Chlorella sp. KR-1 for production of biodiesel.

    Science.gov (United States)

    Lee, Ok Kyung; Kim, Young Hyun; Na, Jeong-Geol; Oh, You-Kwan; Lee, Eun Yeol

    2013-11-01

    We developed a method for the highly efficient lipid extraction and lipase-catalyzed transesterification of triglyceride from Chlorella sp. KR-1 using dimethyl carbonate (DMC). Almost all of the total lipids, approximately 38.9% (w/w) of microalgae dry weight, were extracted from the dried microalgae biomass using a DMC and methanol mixture (7:3 (v/v)). The extracted triglycerides were transesterified into fatty acid methyl esters (FAMEs) using Novozyme 435 as the biocatalyst in DMC. Herein, DMC was used as the reaction medium and acyl acceptor. The reaction conditions were optimized and the FAMEs yield was 293.82 mg FAMEs/g biomass in 6 h of reaction time at 60 °C in the presence of 0.2% (v/v) water. Novozyme 435 was reused more than ten times while maintaining relative FAMEs conversion that was greater than 90% of the initial FAMEs conversion. PMID:23999257

  6. Apolipoprotein AV Accelerates Plasma Hydrolysis OfTriglyceride-Rich Lipoproteins By Interaction With Proteoglycan BoundLipoprotein Lipase

    Energy Technology Data Exchange (ETDEWEB)

    Merkel, Martin; Loeffler, Britta; Kluger, Malte; Fabig, Nathalie; Geppert, Gesa; Pennacchio, Len A.; Laatsch, Alexander; Heeren, Joerg

    2005-02-22

    Apolipoprotein A5 (APOA5) is associated with differences intriglyceride levels and familial combined hyperlipidemia. In genetically engineered mice, apoAV plasma levels are inversely correlated with plasmatriglycerides. To elucidate the mechanism by which apoAV influences plasma triglycerides, metabolic studies and in vitro assays resembling physiological conditions were performed. In hAPOA5 transgenic mice(hAPOA5tr), catabolism of chylomicrons and VLDL was accelerated due to a faster plasma hydrolysis of triglycerides by lipoprotein lipase (LPL).Hepatic VLDL and intestinal chylomicron production were not affected. The functional interplay between apoAV and LPL was further investigated by crossbreeding a human LPL transgene with the apoa5 knockout, and the hAPOA5tr to an LPL deficient background. Increased LPL activity completely normalized hypertriglyceridemia of apoa5 deficient mice,however, over expression of human apoAV modulated triglyceride levels only slightly when LPL was reduced. To reflect the physiological situation in which LPL is bound to cell surface proteoglycans, we examined hydrolysis in the presence or absence of proteoglycans. Without proteoglycans, apoAV derived either from triglyceride-rich lipoproteins, hAPOA5tr HDL, or a recombinant source did not alter the LPL hydrolysis rate. In the presence of proteoglycans, however, apoAV led to a significant and dose-dependent increase in LPL mediated hydrolysis of VLDL triglycerides. These results were confirmed in cell culture using a proteoglycan-deficient cell line.A direct interaction between LPL and apoAV was found by ligand blotting.It is proposed, that apoAV reduces triglyceride levels by guiding VLDL and chylomicrons to proteoglycans bound LPL for lipolysis.

  7. Changes in lipoprotein lipase activity in the adipose tissue, heart and liver of continuously irradiated rats

    International Nuclear Information System (INIS)

    Adult male Wistar rats were continuously irradiated for 30 days on an experimental field from a 60Co source of radiation. Lipoprotein lipase activity was determined in their adipose tissue, heart and liver at intervals of 1, 3, 7, 14, 21 and 30 days from the beginning of irradiation and triacylglycerol, total cholesterol, phospholipid and non-esterified fatty acid concentrations were determined in their serum. Throughout the whole of the study, lipoprotein lipase activity was lower in the adipose tissue and higher in the heart of irradiated rats than in the controls. In the liver it was low 3 days from the onset of irradiation; at the other intervals it was variable and differed only non-significantly from the controls. Serum lipid concentrations were raised in irradiated rats - triacylglycerol from the 7th day, phospholipids from the 14th day and non-esterified fatty acids throughout the whole period of irradiation. In keeping with the high triacylglycerol values in the serum of irradiated rats, lipoprotein lipase activity in their adipose tissue was low. (author)

  8. Metabolism of apolipoproteins B-48 and B-100 of triglyceride-rich lipoproteins in normal and lipoprotein lipase-deficient humans.

    OpenAIRE

    Stalenhoef, A.F.; Malloy, M J; Kane, J P; Havel, R J

    1984-01-01

    The metabolism of apolipoproteins B-48 and B-100 (apo B-48 and B-100) in large triglyceride-rich lipoproteins (300 to 1500 A in diameter) has been compared in three normal subjects and two subjects with genetically determined deficiency of lipoprotein lipase. The triglyceride-rich lipoproteins were obtained from a lipoprotein lipase-deficient donor 4 hr after a fat-rich meal in order to obtain chylomicrons (containing apo B-48) and very low density lipoproteins (VLDL) (containing apo B-100), ...

  9. Lipase

    Science.gov (United States)

    Lipase is a digestive enzyme that is found in many plants, animals, bacteria, and molds. An enzyme ... particular biochemical reaction in the body. People use lipase as a medicine. Lipase is used for indigestion, ...

  10. CD36 deficiency in mice impairs lipoprotein lipase-mediated triglyceride clearance

    NARCIS (Netherlands)

    Goudriaan, [No Value; den Boer, MAM; Rensen, PCN; Febbraio, M; Kuipers, F; Romijn, JA; Havekes, LM; Voshol, PJ

    2005-01-01

    CD36 is involved in high-affinity peripheral FFA uptake. CD36-deficient (cd36(-/-)) mice exhibit increased plasma FFA and triglyceride (TG) levels. The aim of the present study was to elucidate the cause of the increased plasma TG levels in cd36(-/-) mice. cd36(-/-) mice showed no differences in hep

  11. Increased lipolysis but diminished gene expression of lipases in subcutaneous adipose tissue of healthy young males with intrauterine growth retardation

    DEFF Research Database (Denmark)

    Højbjerre, Lise; Alibegovic, Amra C; Sonne, Mette P;

    2011-01-01

    ) and femoral (SCFAT) adipose tissue. Additionally, mRNA expression of lipases was evaluated in biopsies from SCAAT. Lipolysis in SCAAT was substantially higher in IUGR than in CON subjects despite markedly lower mRNA expression of lipases. Blood flow was higher in IUGR compared with CON in both SCAAT and SCFAT...... are characterized by increased in vivo adipose tissue lipolysis and blood flow with a paradoxically decreased expression of lipases compared with CON, and 10 days of physical inactivity underlined the baseline findings. Subjects with IUGR exhibit primary defects in adipose tissue metabolism.......Intrauterine growth retardation (IUGR) is associated with a central fat distribution and risk of developing type 2 diabetes in adults when exposed to a sedentary Western lifestyle. Increased lipolysis is an early defect of metabolism in IUGR subjects, but the sites and molecular mechanisms involved...

  12. The effect of exercise training on hormone-sensitive lipase in rat intra-abdominal adipose tissue and muscle

    DEFF Research Database (Denmark)

    Enevoldsen, L H; Stallknecht, B; Langfort, J;

    2001-01-01

    1. Adrenaline-stimulated lipolysis in adipose tissue may increase with training. The rate-limiting step in adipose tissue lipolysis is catalysed by the enzyme hormone-sensitive lipase (HSL). We studied the effect of exercise training on the activity of the total and the activated form of HSL......, referred to as HSL (DG) and HSL (TG), respectively, and on the concentration of HSL protein in retroperitoneal (RE) and mesenteric (ME) adipose tissue, and in the extensor digitorum longus (EDL) and soleus muscles in rats. 2. Rats (weighing 96 +/- 1 g, mean +/- S.E.M.) were either swim trained (T, 18 weeks......, n = 12) or sedentary (S, n = 12). Then RE and ME adipose tissue and the EDL and soleus muscles were incubated for 20 min with 4.4 microM adrenaline. 3. HSL enzyme activities in adipose tissue were higher in T compared with S rats. Furthermore, in RE adipose tissue, training also doubled HSL protein...

  13. Nitrogen dioxide induced changes in level of free fatty acids, triglyceride, esterified fatty acid, ganglioside and lipase activity in the guinea pig brain

    Energy Technology Data Exchange (ETDEWEB)

    Farahani, H.; Hasan, M. (Interdisciplinary Brain Research Centre, Jawaharlal Nehru Medical College, Aligarh Muslim University, (India))

    1992-02-01

    The biochemical response to controlled inhalation of nitrogen dioxide (NO2) was studied in 18 male guinea pigs. Animals were exposed to 2.5, 5.0, and 10 ppm NO2 for 2h daily for 35 consecutive days, and the results compared with six control animals exposed to filtered air for 2h daily for same period. Five biochemical parameters, including triglyceride, free fatty acids, esterified fatty acid, ganglioside and lipase activity were measured immediately after the last day of exposure. At 2.5 ppm NO2 inhalation no significant changes occurred in any region of the central nervous system (CNS). While as the dose concentration was increased to 5 and 10 ppm nitrogen dioxide, significant dose-related alteration were observed in the levels of triglyceride, free fatty acid, esterified fatty acid, ganglioside and lipase activity in the different regions of the guinea pig CNS.

  14. Hormone-Sensitive Lipase Knockouts

    Directory of Open Access Journals (Sweden)

    Shen Wen-Jun

    2006-02-01

    Full Text Available Abstract All treatments for obesity, including dietary restriction of carbohydrates, have a goal of reducing the storage of fat in adipocytes. The chief enzyme responsible for the mobilization of FFA from adipose tissue, i.e., lipolysis, is thought to be hormone-sensitive lipase (HSL. Studies of HSL knockouts have provided important insights into the functional significance of HSL and into adipose metabolism in general. Studies have provided evidence that HSL, though possessing triacylglycerol lipase activity, appears to be the rate-limiting enzyme for cholesteryl ester and diacylglycerol hydrolysis in adipose tissue and is essential for complete hormone stimulated lipolysis, but other triacylglycerol lipases are important in mediating triacylglycerol hydrolysis in lipolysis. HSL knockouts are resistant to both high fat diet-induced and genetic obesity, displaying reduced quantities of white with increased amounts of brown adipose tissue, increased numbers of adipose macrophages, and have multiple alterations in the expression of genes involved in adipose differentiation, including transcription factors, markers of adipocyte differentiation, and enzymes of fatty acid and triglyceride synthesis. With disruption of lipolysis by removal of HSL, there is a drastic reduction in lipogenesis and alteration in adipose metabolism.

  15. Lipoprotein lipase release from BFC-1 beta adipocytes. Effects of triglyceride-rich lipoproteins and lipolysis products.

    Science.gov (United States)

    Sasaki, A; Goldberg, I J

    1992-07-25

    Lipoprotein lipase (LPL), synthesized by adipocytes and myocytes, must be transported to the luminal endothelial cell surface where it then interacts with circulating lipoproteins. The first step in this extracellular LPL transport pathway is LPL release from the surface of LPL-synthesizing cells. Because hydrolysis of triglyceride (TG)-rich lipoproteins releases LPL from the apical surface of endothelial cells, we hypothesized that the same substances dissociate LPL from adipocytes. 125I-LPL was bound to the surface of brown adipocytes (BFC-1 beta). LPL binding to the adipocyte surface was greater than to endothelial cell surfaces. Using low concentrations of heparin, more LPL was released from endothelial cells than BFC-1 beta, suggesting that the affinity of LPL binding to the adipocytes was greater than LPL affinity for endothelial cells. Greater than 3-fold more LPL was released from the cell surface when very low density lipoproteins (VLDL) were added to culture medium containing 3% bovine serum albumin. LPL remaining on the cell surface decreased with VLDL addition. Endogenously produced LPL activity was also released from the cells by VLDL. Low and high density lipoproteins did not release 125I-LPL or LPL activity from the adipocytes. To assess whether lipolysis was necessary for LPL release, BFC-1 beta were incubated with TG-rich lipoproteins from a patient with apoCII deficiency. The apoCII-deficient lipoproteins did not release LPL unless an exogenous source of apoCII was added. Apolipoproteins E and Cs and high molar ratios of oleic acid:bovine serum albumin did not release surface-associated LPL. Lysolecithin (25 and 100 microM), but not lecithin, monoglycerides, or diglycerides, released adipocyte surface LPL. Because lysolecithin also released LPL during a 4 degrees C incubation, cellular metabolic functions are not required for LPL dissociation from the cells. Lysolecithin also inhibited LPL binding to endothelial cells; however, this effect was

  16. Expression of human hormone-sensitive lipase in white adipose tissue of transgenic mice increases lipase activity but does not enhance in vitro lipolysis.

    Science.gov (United States)

    Lucas, Stéphanie; Tavernier, Geneviève; Tiraby, Claire; Mairal, Aline; Langin, Dominique

    2003-01-01

    Hormone-sensitive lipase (HSL) catalyzes the hydrolysis of acylglycerols and cholesteryl esters (CEs). The enzyme is highly expressed in adipose tissues (ATs), where it is thought to play an important role in fat mobilization. The purpose of the present work was to study the effect of a physiological increase of HSL expression in vivo. Transgenic mice were produced with a 21 kb human genomic fragment encompassing the exons encoding the adipocyte form of HSL. hHSL mRNA was expressed at 3-fold higher levels than murine HSL mRNA in white adipocytes. Transgene expression was also observed in brown adipose tissue (BAT) and skeletal muscle. The human protein was detected in ATs of transgenic (Tg) mice. The hydrolytic activities against triacylglycerol (TG), diacylglycerol (DG) analog, and CE were increased in transgenic mouse AT. However, cAMP-inducible adipocyte lipolysis was lower in transgenic animals. In the B6CBA genetic background, transgenic mice up to 14 weeks of age showed lower body weight and fat mass. The phenotype was not observed in older animals and in mice fed a high-fat diet (HFD). In the OF1 genetic background, there was no difference in fat mass of mice fed ad libitum. However, transgenic mice became leaner than their wild-type (WT) littermates after a 4 day calorie restriction. The data show that overexpression of HSL, despite increased lipase activity, does not lead to enhanced lipolysis. PMID:12518034

  17. A new approach to determine the stereospecificity in lipase catalysed hydrolysis using circular dichroism (CD): lipases produce optically active diglycerides from achiral triglycerides.

    Science.gov (United States)

    Uzawa, H; Nishida, Y; Ohrui, H; Meguro, H

    1990-04-30

    We describe a sensitive CD method for determining the stereospecificity in lipase (E.C.3.1.1.3) catalysed hydrolysis of triacyl glycerols into diacyl glycerols. The diglycerols were converted to chiral tert-butyldimethylsilylated 1,2- or 2,3-di-O-benzoyl-sn-glycerol (5 or 5'), and their CD was measured. This approach showed for the first time that lipases produce optically active diacyl glycerides from achiral tripalmitin and tribenzoyl glyceride with a variable extent of enantioselectivity depending on the acyl groups and the enzymes.

  18. [Prevention of atherosclerosis. The positional specificity of blood triglycerides and lipases, the particular milk lipids, and the modification of the fatty acids of vegetable oils and animal fats].

    Science.gov (United States)

    Titov, V N; Krylin, V V; Shiriaeva, Iu K

    2011-03-01

    Milk is a biological medium that bears no resemblance to any of the biological fluids and tissues in primates and mammals in the positional composition of fatty acids (FA) in triglycerides. This is determined by the fact that at the very early phylogenesis of mammals, milk is to ensure a high postnatal bioavailability (absorption) of saturated palmitic FA, a substrate for neonatal energy supply despite all obstacles that are formed in the baby's intestine in vivo. Milk is destined for infant nutrition in the biology-destined period (not more than a year); assimilation of triglycerides that are so structurally unusual requires a) high isomerization activity in the enterocytes and b) the ability of blood lipases to hydrolyze palmitate-oleate-palmitate triglycerides as a component of oleic very-low-density lipoproteins. After the period permitted by nature, there is virtually no possibility to physiologically consume milk that contains structurally unusual triglycerides. The use of whole milk and its products by adults impairs the active, receptor cell absorption of FAs as ligand lipoproteins via apoE/B-100-endocytosis and enhances the generation of small, dense low-density lipoproteins as biological debris. The impaired biological function of endoecology and the debris accumulation of the intercellular medium lead to the activation of atheromatosis, atherothrombosis, and coronary sclerosis. Nature has given no sanction for turning the mammals that are not on milk to those on milk for whole life. Up to one year of age, the baby has in vivo conditions for the absorption and hydrolysis of triglycerides with palmitic FA at the sn-2 position. After one year of age, the expression of these lipases and coenzymes is over; re-expression occurs only with the activation of the biological function of locomotion - long-term strenuous physical activity. High physical activity expresses other genes, enzymes, coenzymes, and carrier proteins, which activate the hydrolysis of

  19. Inhibition of lipase-catalyzed hydrolysis of emulsified triglyceride oils by low-molecular weight surfactants under simulated gastrointestinal conditions.

    Science.gov (United States)

    Li, Yan; McClements, David Julian

    2011-10-01

    The effect of low-molecular weight surfactants on the digestibility of lipids in protein-stabilized corn oil-in-water emulsions was studied using an in vitro digestion model. The impact of non-ionic (Tween 20, Tween 80, Brij35), anionic (SDS), and cationic (DTAB) surfactants on the rate and extent of lipid digestion was studied. All surfactants were found to inhibit lipid digestion at sufficiently high concentrations, with half-maximal inhibitory concentrations (IC50) of 1.2% for Tween 20, 0.7% for Tween 80, 2.8% for Brij35, 1.1% for SDS, and 1.4% for DTAB. The effectiveness of the surfactants at inhibiting lipid digestion was therefore not strongly correlated to the electrical characteristics of the surfactant head group, since the IC50 increased in the following order: Tween 80>SDS>Tween 20>DTAB>Brij35. The ability of these low-molecular weight surfactants to inhibit lipid digestion was attributed to a number of potential mechanisms: (i) prevention of lipase/co-lipase adsorption to the oil-water interface; (ii) formation of interfacial complexes; (iii) direct interaction and inactivation of lipase/co-lipase. Interestingly, DTAB increased the rate and extent of lipid digestion when present at relatively low concentrations. This may have been because this cationic surfactant facilitated the adsorption of lipase to the droplet surfaces through electrostatic attraction, or it bound directly to the lipase molecule thereby changing its structure and activity. A number of the surfactants themselves were found to be susceptible to enzyme digestion by pancreatic enzymes in the absence of lipids: Tween 20, Tween 80, Brij35, and DTAB. This work has important implications for the development of emulsion-based delivery systems for food and pharmaceutical applications.

  20. Dissecting adipose tissue lipolysis: molecular regulation and implications for metabolic disease

    DEFF Research Database (Denmark)

    Nielsen, Thomas Svava; Jessen, Niels; Jørgensen, Jens Otto Lunde;

    2014-01-01

    is tightly regulated by hormonal and nutritional factors. Under conditions of negative energy balance such as fasting and exercise, stimulation of lipolysis results in a profound increase in FFA release from adipose tissue. This response is crucial in order to provide the organism with a sufficient supply...... localization, protein-protein interactions, and protein stability/degradation. Here, we provide an overview of the recent advances in the field of adipose tissue lipolysis with particular focus on the molecular regulation of the two main lipases, ATGL and HSL and the intracellular and extracellular signals......Lipolysis is the process by which triglycerides are hydrolyzed to free fatty acids (FFA) and glycerol. In adipocytes, this is achieved by the sequential action of Adipose Triglyceride Lipase (ATGL), Hormone Sensitive Lipase (HSL) and Monoglyceride Lipase (MGL). The activity in the lipolytic pathway...

  1. Adipose Overexpression of Desnutrin Promotes Fatty Acid Use and Attenuates Diet-Induced Obesity

    OpenAIRE

    Ahmadian, Maryam; Duncan, Robin E.; Varady, Krista A.; Frasson, Danubia; Hellerstein, Marc K.; Birkenfeld, Andreas L.; Samuel, Varman T.; Shulman, Gerald I.; Wang, Yuhui; Kang, Chulho; Sul, Hei Sook

    2009-01-01

    OBJECTIVE To investigate the role of desnutrin in adipose tissue triacylglycerol (TAG) and fatty acid metabolism. RESEARCH DESIGN AND METHODS We generated transgenic mice overexpressing desnutrin (also called adipose triglyceride lipase [ATGL]) in adipocytes (aP2-desnutrin) and also performed adenoviral-mediated overexpression of desnutrin in 3T3-L1CARΔ1 adipocytes. RESULTS aP2-desnutrin mice were leaner with decreased adipose tissue TAG content and smaller adipocyte size. Overexpression of d...

  2. Effect of di(2-ethylhexyl) phthalate (DEHP) on lipolysis and lipoprotein lipase activities in adipose tissue of rats.

    Science.gov (United States)

    Martinelli, Marcela I; Mocchiutti, Norberto O; Bernal, Claudio A

    2010-09-01

    The di(2-ethylhexyl) phthalate (DEHP) is an ubiquitous environmental chemical with detrimental health effects. The present work was designed to asses some potential mechanisms by which DEHP causes, among others, a reduced body fat retention. Since this effect could be related to an alteration of adipocyte triacylglycerol (TG) metabolism, we evaluated the effects of dietary DEHP in adipose tissues upon (1) the number and size of fat cells; (2) the basal and stimulated lipolysis and (3) the lipoprotein lipase (LPL) activity. Groups of male Wistar rats were fed for 21 days a control diet alone (control group) or the same control diet supplemented with 2% (w/w) of DEHP (DEHP group). The LPL activity of DEHP-fed rats was increased in lumbar and epididymal adipose tissues. These rats had significantly reduced weight in epididymal and lumbar tissues, together with reduced size of epididymal adipocytes. These alterations do not seem to be associated with higher lipid mobility because neither basal lipolysis nor 'in vitro' stimulated lipolysis by noradrenaline (NA) showed to be modified by DEHP. Based on these results, we concluded that the adipose tissue size reduction induced by DEHP intake is not due to changes in lipolysis nor to a decreased LPL activity. More research is needed to achieve a comprehensive understanding of the potential mechanisms by which DEHP causes, among others, a reduced body fat retention. PMID:20144957

  3. Changes in lipoprotein lipase activity in the adipose tissue and heart of non-lethally X-irradiated rats

    International Nuclear Information System (INIS)

    After 16 h of nocturnal food deprivation, male Wistar rats were irradiated with a single whole-body dose of 2.40 Gy of X-rays. Both the irradiated and sham-irradiated (control) rats were pair-fed for the first six days after irradiation, but for the rest of the time they were fed ad libitum. Lipoprotein lipase activity (LPLA) in the adipose tissue fell between 24 and 48 h; LPLA in the heart fell at 24 h and 21 days and rose on the 14th day. The serum triacylglycerol concentration rose between 24 and 72 h. A comparison with the fed control group showed LPLA in adipose tissue to be reduced at 6 and 72 h and on the 28th day and raised between the 7th and the 14th day. In the heart it was raised at 1 h and between 72h and the 14th day, it was reduced on the 21st day and rose on the 35th day. The triacylglycerol concentration was raised between 48 and 72 h and on the 28th day. Pair-feeding after non-lethal X-irradiation allowed more exact differentiation of the specific effect of ionizing radiation on LPLA in the adipose tissue and heart at early post-irradiation intervals. (author)

  4. Adipocyte lipases and defect of lipolysis in human obesity.

    Science.gov (United States)

    Langin, Dominique; Dicker, Andrea; Tavernier, Geneviève; Hoffstedt, Johan; Mairal, Aline; Rydén, Mikael; Arner, Erik; Sicard, Audrey; Jenkins, Christopher M; Viguerie, Nathalie; van Harmelen, Vanessa; Gross, Richard W; Holm, Cecilia; Arner, Peter

    2005-11-01

    The mobilization of fat stored in adipose tissue is mediated by hormone-sensitive lipase (HSL) and the recently characterized adipose triglyceride lipase (ATGL), yet their relative importance in lipolysis is unknown. We show that a novel potent inhibitor of HSL does not inhibit other lipases. The compound counteracted catecholamine-stimulated lipolysis in mouse adipocytes and had no effect on residual triglyceride hydrolysis and lipolysis in HSL-null mice. In human adipocytes, catecholamine- and natriuretic peptide-induced lipolysis were completely blunted by the HSL inhibitor. When fat cells were not stimulated, glycerol but not fatty acid release was inhibited. HSL and ATGL mRNA levels increased concomitantly during adipocyte differentiation. Abundance of the two transcripts in human adipose tissue was highly correlated in habitual dietary conditions and during a hypocaloric diet, suggesting common regulatory mechanisms for the two genes. Comparison of obese and nonobese subjects showed that obesity was associated with a decrease in catecholamine-induced lipolysis and HSL expression in mature fat cells and in differentiated preadipocytes. In conclusion, HSL is the major lipase for catecholamine- and natriuretic peptide-stimulated lipolysis, whereas ATGL mediates the hydrolysis of triglycerides during basal lipolysis. Decreased catecholamine-induced lipolysis and low HSL expression constitute a possibly primary defect in obesity. PMID:16249444

  5. Characterization of Lipoprotein Lipases interactions with Sortilin and SorLA

    DEFF Research Database (Denmark)

    Klinger, Stine Christensen

    . The present study describes their trafficking of two ligands, lipoprotein lipase and apolipoprotein A-V, which are integral parts of the lipid metabolism. Lipoprotein lipase is found at the luminal side of capillary endothelial cells, where it is involved in the conversion of circulating triglycerides to free...... fatty acids, which in turn are used as an energy source in muscle cells or as an energy reserve in adipose tissue. Lack of lipoprotein lipase leads to an elevated level of plasma lipids and results in increased risk of cardiovascular diseases. The regulation of lipoprotein lipase expression takes place...... at both transcriptional and posttranslational levels. While the transcriptional regulation of the lipase is well described, the posttranslational mechanisms affecting lipoprotein lipase expression are far from understood. The functions of the recently discovered apolipoprotein A-V are still a subject...

  6. Placental lipases in pregnancies complicated by gestational diabetes mellitus (GDM.

    Directory of Open Access Journals (Sweden)

    Helen L Barrett

    Full Text Available Infants of women with gestational diabetes mellitus (GDM are more likely to be born large for gestational age with a higher percentage body fat. Elevated maternal lipids may contribute to this. Placental lipases such as lipoprotein lipase (LPL, endothelial lipase (EL and hormone sensitive lipase (HSL are involved in transferring lipids from mother to fetus. Previous studies of expression of these lipases in placentae in women with diabetes in pregnancy have reported divergent results. Intracellular lipases such as adipose triglyceride lipase (ATGL, and HSL are central to lipid droplet metabolism. The activities of these lipases are both influenced by Perilipin 1, and ATGL is also activated by a co-factor comparative gene identification-58 (CGI-58 and inhibited by G0/G1 switch gene 2 (GS02. None of these modifying factors or ATGL have been examined previously in placenta. The purpose of this study was therefore to examine the expression of ATGL, HSL, LPL, EL, as well as Perilipin 1, GS02 and CGI-58 in term pregnancies complicated by GDM. mRNA and protein expression of the lipases were measured in placentae from 17 women with GDM and 17 normoglycaemic pregnancies, matched for maternal BMI and gestational age of delivery. ATGL mRNA expression was increased and HSL mRNA expression reduced in placentae from GDM although there was no differences in protein expression of any of the lipases. All lipases were localised to trophoblasts and endothelial cells. The expression of Perilipin 1 and CGI-58 mRNA was increased and GS02 not altered in GDM. These results suggest that there is no difference in expression in these four lipases between GDM and normoglycaemic placentae, and therefore altered lipid transfer via these lipases does not contribute to large for gestational age in infants of women with GDM.

  7. Combined analysis of six lipoprotein lipase genetic variants on triglycerides, high-density lipoprotein, and ischemic heart disease: cross-sectional, prospective, and case-control studies from the Copenhagen City Heart Study

    DEFF Research Database (Denmark)

    Wittrup, HH; Andersen, RV; Tybjærg-Hansen, A;

    2006-01-01

    CONTEXT: Genetic variants in lipoprotein lipase may affect triglycerides, high-density lipoprotein (HDL), and risk of ischemic heart disease (IHD). OBJECTIVE: The objective of this study was to investigate the influence of T(-93)G, G(-53)C, Asp9Asn, Gly188Glu, Asn291Ser, and Ser447Ter lipoprotein....... SETTING: The study was performed in the Danish general population (the Copenhagen City Heart Study). PARTICIPANTS: IHD was angina pectoris or myocardial infarction. MAIN OUTCOME MEASURES: Triglycerides, HDL, and IHD were the main outcome measures. RESULTS: Cross-sectionally, triglycerides varied...... by genotype with 1.27 mmol/liter in women and 1.22 mmol/liter in men. HDL cholesterol varied by genotype with 0.49 mmol/liter in women and 0.60 mmol/liter in men. Prospectively, 9Asn (with -93G) heterozygotes and homozygotes combined vs. noncarriers had a hazard ratio for IHD of 1.6 [95% confidence interval...

  8. Hormonal regulation of lipoprotein lipase in adipose tissue (studies in the rat and in humans)

    NARCIS (Netherlands)

    M.G.A. Baggen (Marinus)

    1988-01-01

    textabstractCurrent data strongly suggest the most important role for insulin in the hormonal regulation of adipose tissue LPL activity. It is not clear from the literature what the role is of glucocorticoids in the regulation of the enzyme. Stress hormones as ACTH and adrenalin for example seem to

  9. Covalent immobilization of lipase, glycerol kinase, glycerol-3-phosphate oxidase & horseradish peroxidase onto plasticized polyvinyl chloride (PVC strip & its application in serum triglyceride determination

    Directory of Open Access Journals (Sweden)

    Nidhi Chauhan

    2014-01-01

    Full Text Available Background & objectives:Reusable biostrip consisting enzymes immobilized onto alkylamine glass beads affixed on plasticized PVC strip for determination of triglyceride (TG suffers from high cost of beads and their detachments during washings for reuse, leading to loss of activity. The purpose of this study was to develop a cheaper and stable biostrip for investigation of TG levels in serum. Methods: A reusable enzyme-strip was prepared for TG determination by co-immobilizing lipase, glycerol kinase (GK, glycerol-3-phosphate oxidase (GPO and peroxidase (HRP directly onto plasticized polyvinyl chloride (PVC strip through glutaraldehyde coupling. The method was evaluated by studying its recovery, precision and reusability. Results: The enzyme-strip showed optimum activity at pH 7.0, 35 o C and a linear relationship between its activity and triolein concentration in the range 0.1 to 15 mM. The strip was used for determination of serum TG. The detection limit of the method was 0.1 mM. Analytical recovery of added triolein was 96 per cent. Within and between batch coefficients of variation (CV were 2.2 and 3.7 per cent, respectively. A good correlation (r=0.99 was found between TG values by standard enzymic colrimetric method employing free enzymes and the present method. The strip lost 50 per cent of its initial activity after its 200 uses during the span of 100 days, when stored at 4 o C. Interpretation & conclusions: The nitrating acidic treatment of plasticized PVC strip led to glutaraldehyde coupling of four enzymes used for enzymic colourimetric determination of serum TG. The strip provided 200 reuses of enzymes with only 50 per cent loss of its initial activity. The method could be used for preparation of other enzyme strips also.

  10. Radiochemical determination of lipoprotein lipase activity (LPLA) in human adipose tissue

    International Nuclear Information System (INIS)

    Lipoprotein lipase activity (LPLA) is measured in samples (20 to 100 mg) of human fatty tissue obtained by needle biopsy. The material is converted into an acetone-ether powder by defatting. 3H-labelled triolein which is suspended in glycerol, using inactive triolein, lecithin and ultrasonication, serves as a substrate concentrate, from which a substrate is prepared by adding Tris buffer, albumin and serum. The amount of oleic acid liberated from the suspended acetone-ether powder during incubation is measured by its radioactivity. 78 determinations in patients with hyperlipoproteinemia yielded a mean LPLA value of 0.606 +- 0.501 μmoles/g-1h-1. (author)

  11. Human hormone-sensitive lipase (HSL): expression in white fat corrects the white adipose phenotype of HSL-deficient mice.

    Science.gov (United States)

    Fortier, Mélanie; Soni, Krishnakant; Laurin, Nancy; Wang, Shu Pei; Mauriège, Pascale; Jirik, Frank R; Mitchell, Grant A

    2005-09-01

    In white adipose tissue (WAT), hormone-sensitive lipase (HSL) can mediate lipolysis, a central pathway in obesity and diabetes. Gene-targeted HSL-deficient (HSL-/-) mice with no detectable HSL peptide or activity (measured as cholesteryl esterase) have WAT abnormalities, including low mass, marked heterogeneity of cell diameter, increased diacylglycerol content, and low beta-adrenergic stimulation of adipocyte lipolysis. Three transgenic mouse strains preferentially expressing human HSL in WAT were bred to a HSL-/- background. One, HSL-/- N, expresses normal human HSL (41.3 +/- 9.1% of normal activity); two express a serine-to-alanine mutant (S554A) initially hypothesized to be constitutively active: HSL-/- ML, 50.3 +/- 12.3% of normal, and HSL-/- MH, 69.8 +/- 15.8% of normal. In WAT, HSL-/- N mice resembled HSL+/+ controls in WAT mass, histology, diacylglyceride content, and lipolytic response to beta-adrenergic agents. In contrast, HSL-/- ML and HSL-/- MH mice resembled nontransgenic HSL-/- mice, except that diacylglycerol content and perirenal and inguinal WAT masses approached normal in HSL-/- MH mice. Therefore, 1) WAT expression of normal human HSL markedly improves HSL-/- WAT biochemically, physiologically, and morphologically; 2) similar levels of S554A HSL have a low physiological effect despite being active in vitro; and 3) diacylglycerol accumulation is not essential for the development of the characteristic WAT pathology of HSL-/- mice.

  12. Inborn errors of cytoplasmic triglyceride metabolism.

    Science.gov (United States)

    Wu, Jiang Wei; Yang, Hao; Wang, Shu Pei; Soni, Krishnakant G; Brunel-Guitton, Catherine; Mitchell, Grant A

    2015-01-01

    Triglyceride (TG) synthesis, storage, and degradation together constitute cytoplasmic TG metabolism (CTGM). CTGM is mostly studied in adipocytes, where starting from glycerol-3-phosphate and fatty acyl (FA)-coenzyme A (CoA), TGs are synthesized then stored in cytoplasmic lipid droplets. TG hydrolysis proceeds sequentially, producing FAs and glycerol. Several reactions of CTGM can be catalyzed by more than one enzyme, creating great potential for complex tissue-specific physiology. In adipose tissue, CTGM provides FA as a systemic energy source during fasting and is related to obesity. Inborn errors and mouse models have demonstrated the importance of CTGM for non-adipose tissues, including skeletal muscle, myocardium and liver, because steatosis and dysfunction can occur. We discuss known inborn errors of CTGM, including deficiencies of: AGPAT2 (a form of generalized lipodystrophy), LPIN1 (childhood rhabdomyolysis), LPIN2 (an inflammatory condition, Majeed syndrome, described elsewhere in this issue), DGAT1 (protein loosing enteropathy), perilipin 1 (partial lipodystrophy), CGI-58 (gene ABHD5, neutral lipid storage disease (NLSD) with ichthyosis and "Jordan's anomaly" of vacuolated polymorphonuclear leukocytes), adipose triglyceride lipase (ATGL, gene PNPLA2, NLSD with myopathy, cardiomyopathy and Jordan's anomaly), hormone-sensitive lipase (HSL, gene LIPE, hypertriglyceridemia, and insulin resistance). Two inborn errors of glycerol metabolism are known: glycerol kinase (GK, causing pseudohypertriglyceridemia) and glycerol-3-phosphate dehydrogenase (GPD1, childhood hepatic steatosis). Mouse models often resemble human phenotypes but may diverge markedly. Inborn errors have been described for less than one-third of CTGM enzymes, and new phenotypes may yet be identified. PMID:25300978

  13. Inborn errors of cytoplasmic triglyceride metabolism.

    Science.gov (United States)

    Wu, Jiang Wei; Yang, Hao; Wang, Shu Pei; Soni, Krishnakant G; Brunel-Guitton, Catherine; Mitchell, Grant A

    2015-01-01

    Triglyceride (TG) synthesis, storage, and degradation together constitute cytoplasmic TG metabolism (CTGM). CTGM is mostly studied in adipocytes, where starting from glycerol-3-phosphate and fatty acyl (FA)-coenzyme A (CoA), TGs are synthesized then stored in cytoplasmic lipid droplets. TG hydrolysis proceeds sequentially, producing FAs and glycerol. Several reactions of CTGM can be catalyzed by more than one enzyme, creating great potential for complex tissue-specific physiology. In adipose tissue, CTGM provides FA as a systemic energy source during fasting and is related to obesity. Inborn errors and mouse models have demonstrated the importance of CTGM for non-adipose tissues, including skeletal muscle, myocardium and liver, because steatosis and dysfunction can occur. We discuss known inborn errors of CTGM, including deficiencies of: AGPAT2 (a form of generalized lipodystrophy), LPIN1 (childhood rhabdomyolysis), LPIN2 (an inflammatory condition, Majeed syndrome, described elsewhere in this issue), DGAT1 (protein loosing enteropathy), perilipin 1 (partial lipodystrophy), CGI-58 (gene ABHD5, neutral lipid storage disease (NLSD) with ichthyosis and "Jordan's anomaly" of vacuolated polymorphonuclear leukocytes), adipose triglyceride lipase (ATGL, gene PNPLA2, NLSD with myopathy, cardiomyopathy and Jordan's anomaly), hormone-sensitive lipase (HSL, gene LIPE, hypertriglyceridemia, and insulin resistance). Two inborn errors of glycerol metabolism are known: glycerol kinase (GK, causing pseudohypertriglyceridemia) and glycerol-3-phosphate dehydrogenase (GPD1, childhood hepatic steatosis). Mouse models often resemble human phenotypes but may diverge markedly. Inborn errors have been described for less than one-third of CTGM enzymes, and new phenotypes may yet be identified.

  14. Fatty acid composition of adipose tissue triglycerides in obese diabetic women after bariatric surgery: a 2-year follow up.

    Science.gov (United States)

    Kunešová, M; Sedláčková, B; Bradnová, O; Tvrzická, E; Staňková, B; Šrámková, P; DoleŽalová, K; Kalousková, P; Hlavatý, P; Hill, M; Bendlová, B; Fried, M; Hainer, V; Vrbíková, J

    2015-01-01

    Bariatric surgery is the most effective method in the treatment of obesity and type 2 diabetes (T2DM). The aim of this study was to evaluate the effects of different types of bariatric procedures on remission of T2DM and on the fatty acid composition in subcutaneous adipose tissue. Patients included obese diabetic women who underwent bariatric surgery: biliopancreatic diversion (BPD), n=8, laparoscopic gastric banding (LAGB), n=9 or laparoscopic greater curvature plication (LGCP), n=12. Anthropometric characteristics and fatty acid composition of adipose tissue (FA AT) were analyzed before surgery, then 6 months and 2 years after surgery. FA AT was analyzed by gas chromatography. Diabetes remission was estimated. BPD was most efficient in inducing a remission of diabetes (p=0.004). Significantly higher increases in lauric (12:0), myristoleic (14:1n-5) and palmitoleic (16:1n-7) acids and delta-9 desaturase were found two years after BPD, suggesting higher lipogenesis in adipose tissue. Docosatetraenoic acid (22:4n-6) increased significantly after BPD, while docosapentaenoic acid (22:5n-3) decreased 6 months after BPD and increased after 2 years. No changes were found after LAGB and LGCP after 2 years. Bariatric surgery led to significant changes in the fatty acid composition of subcutaneous adipose tissue in severely obese diabetic women after six months and two years, and was partly influenced by the type of surgery used. PMID:26680476

  15. Removal of Intra-abdominal Visceral Adipose Tissue Improves Glucose Tolerance in Rats: Role of Hepatic Triglyceride Storage

    OpenAIRE

    Foster, Michelle T.; Shi, Haifei; Seeley, Randy J.; Woods, Stephen C.

    2011-01-01

    Epidemiological studies have demonstrated a strong link between increased visceral fat and metabolic syndrome. In rodents, removal of intra-abdominal but non-visceral fat improves insulin sensitivity and glucose homeostasis, though previous studies make an imprecise comparison to human physiology because actual visceral fat was not removed. We hypothesize that nutrient release from visceral adipose tissue may have greater consequences on metabolic regulation than nutrient release from non-vis...

  16. 脂肪甘油三酯脂肪酶( ATGL)的生物学功能及调控机制%Biological Functions and Regulation of Adipose Triacylglyceride Lipase

    Institute of Scientific and Technical Information of China (English)

    胡深强; 潘志雄; 王继文

    2011-01-01

    脂肪甘油三酯脂肪酶(ATGL)是近年来研究发现的启动脂肪动员的又一关键脂肪酶.ATGL能特异性地水解甘油三酯(TAG)的第一酯键,被认为是TAG水解过程的限速酶.ATGL在脂肪组织和非脂肪组织脂代谢过程中都发挥着重要作用,其活性和表达在细胞内受到转录水平、翻译后水平等调控.ATGL介导的脂解过程可能与肥胖、糖尿病、脂肪肝等代谢疾病存在关联.本文主要就ATGL的结构特征、生物学功能及其调控机制进行综述,并对今后的研究方向和应用进行了展望.%Recent studies showed that adipose triacylglyceride lipase ( ATGL) functioned as an additional key enzyme for adipose lipid mobilization. ATGL specifically hydrolyzes the first ester bond of triglycerides and is a rate-limiting enzyme in triacylglycerol hydrolysis. The wide expression of ATGL suggested its important role in lipid metabolism in various tissue and cell types. The expression and activity of ATGL are regulated at both transcriptional and posttranslational levels. ATGL are also found to associate with obesity, diabetes, hepatic steatosis, and other related metabolic disorders. We focus on the discussion of structural characteristics, expression, biological functions, and regulatory mechanism of ATGL, and prospect on its potential application in the future.

  17. Comparative Analyses of Lipoprotein Lipase, Hepatic Lipase, and Endothelial Lipase, and Their Binding Properties with Known Inhibitors

    OpenAIRE

    Wang, Ziyun; Li, Shen; Sun, Lidan; Fan, Jianglin; Liu, Zhenming

    2013-01-01

    The triglyceride lipase gene subfamily plays a central role in lipid and lipoprotein metabolism. There are three members of this subfamily: lipoprotein lipase, hepatic lipase, and endothelial lipase. Although these lipases are implicated in the pathophysiology of hyperlipidemia and atherosclerosis, their structures have not been fully solved. In the current study, we established homology models of these three lipases, and carried out analysis of their activity sites. In addition, we investiga...

  18. Nitro-Oleic Acid Reduces J774A.1 Macrophage Oxidative Status and Triglyceride Mass: Involvement of Paraoxonase2 and Triglyceride Metabolizing Enzymes.

    Science.gov (United States)

    Rosenblat, Mira; Rom, Oren; Volkova, Nina; Aviram, Michael

    2016-08-01

    Nitro-fatty acids possess anti-atherogenic properties, but their effects on macrophage oxidative status and lipid metabolism that play important roles in atherosclerosis development are unclear. This study compared the effects of nitro-oleic acid (OLA-NO2) with those of native oleic acid (OLA) on intracellular reactive oxygen species (ROS) generation, anti-oxidants and metabolism of triglycerides and cholesterol in J774A.1 macrophages. Upon incubating the cells with physiological concentrations of OLA-NO2 (0-1 µM) or with equivalent levels of OLA, ROS levels measured by 2, 7-dichlorofluorescein diacetate, decreased dose-dependently, but the anti-oxidative effects of OLA-NO2 were significantly augmented. Copper ion addition increased ROS generation in OLA treated macrophages without affecting OLA-NO2 treated cells. These effects could be attributed to elevated glutathione levels and to increased activity and expression of paraoxonase2 that were observed in OLA-NO2 vs OLA treated cells. Beneficial effects on triglyceride metabolism were noted in OLA-NO2 vs OLA treated macrophages in which cellular triglycerides were reduced due to attenuated biosynthesis and accelerated hydrolysis of triglycerides. Accordingly, OLA-NO2 treated cells demonstrated down-regulation of diacylglycerol acyltransferase1, the key enzyme in triglyceride biosynthesis, and increased expression of hormone-sensitive lipase and adipose triglyceride lipase that regulate triglyceride hydrolysis. Finally, OLA-NO2 vs OLA treatment resulted in modest but significant beneficial effects on macrophage cholesterol metabolism, reducing cholesterol biosynthesis rate and low density lipoprotein influx into the cells, while increasing high density lipoprotein-mediated cholesterol efflux from the macrophages. Collectively, compared with OLA, OLA-NO2 modestly but significantly reduces macrophage oxidative status and cellular triglyceride content via modulation of cellular anti-oxidants and triglyceride

  19. Nitro-Oleic Acid Reduces J774A.1 Macrophage Oxidative Status and Triglyceride Mass: Involvement of Paraoxonase2 and Triglyceride Metabolizing Enzymes.

    Science.gov (United States)

    Rosenblat, Mira; Rom, Oren; Volkova, Nina; Aviram, Michael

    2016-08-01

    Nitro-fatty acids possess anti-atherogenic properties, but their effects on macrophage oxidative status and lipid metabolism that play important roles in atherosclerosis development are unclear. This study compared the effects of nitro-oleic acid (OLA-NO2) with those of native oleic acid (OLA) on intracellular reactive oxygen species (ROS) generation, anti-oxidants and metabolism of triglycerides and cholesterol in J774A.1 macrophages. Upon incubating the cells with physiological concentrations of OLA-NO2 (0-1 µM) or with equivalent levels of OLA, ROS levels measured by 2, 7-dichlorofluorescein diacetate, decreased dose-dependently, but the anti-oxidative effects of OLA-NO2 were significantly augmented. Copper ion addition increased ROS generation in OLA treated macrophages without affecting OLA-NO2 treated cells. These effects could be attributed to elevated glutathione levels and to increased activity and expression of paraoxonase2 that were observed in OLA-NO2 vs OLA treated cells. Beneficial effects on triglyceride metabolism were noted in OLA-NO2 vs OLA treated macrophages in which cellular triglycerides were reduced due to attenuated biosynthesis and accelerated hydrolysis of triglycerides. Accordingly, OLA-NO2 treated cells demonstrated down-regulation of diacylglycerol acyltransferase1, the key enzyme in triglyceride biosynthesis, and increased expression of hormone-sensitive lipase and adipose triglyceride lipase that regulate triglyceride hydrolysis. Finally, OLA-NO2 vs OLA treatment resulted in modest but significant beneficial effects on macrophage cholesterol metabolism, reducing cholesterol biosynthesis rate and low density lipoprotein influx into the cells, while increasing high density lipoprotein-mediated cholesterol efflux from the macrophages. Collectively, compared with OLA, OLA-NO2 modestly but significantly reduces macrophage oxidative status and cellular triglyceride content via modulation of cellular anti-oxidants and triglyceride

  20. PPARγ activation alters fatty acid composition in adipose triglyceride, in addition to proliferation of small adipocytes, in insulin resistant high-fat fed rats.

    Science.gov (United States)

    Sato, Daisuke; Oda, Kanako; Kusunoki, Masataka; Nishina, Atsuyoshi; Takahashi, Kazuaki; Feng, Zhonggang; Tsutsumi, Kazuhiko; Nakamura, Takao

    2016-02-15

    It was reported that adipocyte size is potentially correlated in part to amount of long chain polyunsaturated fatty acids (PUFAs) and insulin resistance because several long chain PUFAs can be ligands of peroxisome proliferator-activated receptors (PPARs). In our previous study, marked reduction of PUFAs was observed in insulin-resistant high-fat fed rats, which may indicate that PUFAs are consumed to improve insulin resistance. Although PPARγ agonist, well known as an insulin sensitizer, proliferates small adipocytes, the effects of PPARγ agonist on FA composition in adipose tissue have not been clarified yet. In the present study, we administered pioglitazone, a PPARγ agonist, to high-fat fed rats, and measured their FA composition of triglyceride fraction in adipose tissue and adipocyte diameters in pioglitazone-treated (PIO) and non-treated (control) rats. Insulin sensitivity was obtained with hyperinsulinemic euglycemic clamp. Average adipocyte diameter in the PIO group were smaller than that in the control one without change in tissue weight. In monounsaturated FAs (MUFAs), 14:1n-5, 16:1n-7, and 18:1n-9 contents in the PIO group were lower than those, respectively, in the control group. In contrast, 22:6n-3, 20:3n-6, 20:4n-6, and 22:4n-6 contents in the PIO group were higher than those, respectively, in the control group. Insulin sensitivity was higher in the PIO group than in the control one. These findings suggest that PPARγ activation lowered MUFAs whereas suppressed most of C20 or C22 PUFAs reduction, and that the change of fatty acid composition may be relevant with increase in small adipocytes. PMID:26825545

  1. Radix Astragali Improves Dysregulated Triglyceride Metabolism and Attenuates Macrophage Infiltration in Adipose Tissue in High-Fat Diet-Induced Obese Male Rats through Activating mTORC1-PPARγ Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Yang Long

    2014-01-01

    Full Text Available Increased levels of free fatty acids (FFAs and hypertriglyceridemia are important risk factors for cardiovascular disease. The effective fraction isolated from radix astragali (RA has been reported to alleviate hypertriglyceridemia. The mechanism of this triglyceride-lowering effect of RA is unclear. Here, we tested whether activation of the mTORC1-PPARγ signaling pathway is related to the triglyceride-lowering effect of RA. High-fat diet-induced obese (DIO rats were fed a high-fat diet (40% calories from fat for 9-10 weeks, and 4 g/kg/d RA was administered by gavage. RA treatment resulted in decreased fasting triglyceride levels, FFA concentrations, and adipocyte size. RA treated rats showed improved triglyceride clearance and fatty acid handling after olive oil overload. RA administration could also decrease macrophage infiltration and expression of MCP-1 and TNFα, but it may also increase the expression of PPARγ in epididymal adipose tissue from RA treated rats. Consistently, expressions of PPARγ and phospho-p70S6K were increased in differentiated 3T3-L1 adipocytes treated with RA. Moreover, RA couldnot upregulate the expression of PPARγ at the presence of rapamycin. In conclusion, the mTORC1-PPARγ signaling pathway is a potential mechanism through which RA exerts beneficial effects on the disturbance of triglyceride metabolism and dysfunction of adipose tissue in DIO rats.

  2. Relationship of adiposity to the population distribution of plasma triglyceride concentrations in vigorously active men and women

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Paul T.

    2002-12-21

    Context and Objective: Vigorous exercise, alcohol and weight loss are all known to increase HDL-cholesterol, however, it is not known whether these interventions raise low HDL as effectively as has been demonstrated for normal HDL. Design: Physician-supplied medical data from 7,288 male and 2,359 female runners were divided into five strata according to their self-reported usual running distance, reported alcohol intake, body mass index (BMI) or waist circumference. Within each stratum, the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles for HDL-cholesterol were then determined. Bootstrap resampling of least-squares regression was applied to determine the cross-sectional relationships between these factors and each percentile of the HDL-cholesterol distribution. Results: In both sexes, the rise in HDL-cholesterol per unit of vigorous exercise or alcohol intake was at least twice as great at the 95th percentile as at the 5th percentile of the HDL-distribution. There was also a significant graded increase in the slopes relating exercise (km run) and alcohol intake to HDL between the 5th and the 95th percentile. Men's HDL-cholesterol decreased in association with fatness (BMI and waist circumference) more sharply at the 95th than at the 5th percentile of the HDL-distribution. Conclusions: Although exercise, alcohol and adiposity were all related to HDL-cholesterol, the elevation in HDL per km run or ounce of alcohol consumed, and reduction in HDL per kg of body weight (men only), was least when HDL was low and greatest when HDL was high. These cross-sectional relationships support the hypothesis that men and women who have low HDL-cholesterol will be less responsive to exercise and alcohol (and weight loss in men) as compared to those who have high HDL-cholesterol.

  3. Effect of Bariatric Weight Loss on the Adipose Lipolytic Transcriptome in Obese Humans

    Directory of Open Access Journals (Sweden)

    Shakun Karki

    2015-01-01

    Full Text Available Background. Dysregulated lipolysis has been implicated in mechanisms of cardiometabolic disease and inflammation in obesity. Purpose. We sought to examine the effect of bariatric weight loss on adipose tissue lipolytic gene expression and their relationship to systemic metabolic parameters in obese subjects. Methods/Results. We biopsied subcutaneous adipose tissue in 19 obese individuals (BMI 42 ± 5 kg/m2, 79% female at baseline and after a mean period of 8 ± 5 months (range 3–15 months following bariatric surgery. We performed adipose tissue mRNA expression of proteins involved in triglyceride hydrolysis and correlated their weight loss induced alterations with systemic parameters associated with cardiovascular disease risk. mRNA transcripts of adipose triglyceride lipase (ATGL, hormone-sensitive lipase (HSL, and lipid droplet proteins comparative gene identification 58 (CGI-58 and perilipin increased significantly after weight loss (p<0.05 for all. ATGL expression correlated inversely with plasma triglyceride (TG, hemoglobin A1C (HbA1C, and glucose, and HSL expression correlated negatively with glucose, while CGI-58 was inversely associated with HbA1C. Conclusion. We observed increased expression of adipose tissue lipolytic genes following bariatric weight loss which correlated inversely with systemic markers of lipid and glucose metabolism. Functional alterations in lipolysis in human adipose tissue may play a role in shaping cardiometabolic phenotypes in human obesity.

  4. Effects of insulin-induced hypoglycaemia on lipolysis rate, lipid oxidation and adipose tissue signalling in human volunteers: a randomised clinical study

    DEFF Research Database (Denmark)

    Voss, Thomas S; Vendelbo, Mikkel H; Opstrup, Ulla Kampmann;

    2016-01-01

    adipose tissue biopsies, we found elevated levels of hormone-sensitive lipase (HSL) and perilipin-1 phosphorylation 30 min after insulin injection during HH compared with both control and HE. There were no changes in the levels of adipose triglyceride lipase (ATGL), comparative gene identification-58 (CGI....... CONCLUSIONS/INTERPRETATION: These findings suggest that NEFAs become a major fuel source during insulin-induced hypoglycaemia and that lipolysis may be an important component of the counter-regulatory response. These effects appear to be mediated by rapid stimulation of protein kinase A (PKA) and HSL...

  5. The effect of a single lethal X-irradiation exposure on the activity of lipoprotein lipase in the tissues of the rat

    International Nuclear Information System (INIS)

    Wistar male rats, both fed and fasting for 16 h prior to irradiation, were exposed to a single lethal X-ray dose of 387 mC/kg (1500R). The activity of lipoprotein lipase in white adipose (epididymal) tissue and heart muscle and the concentration of serum triglycerides were determined at 1, 6, 24, 48, and 72 h after irradiation. In the early time periods, at 1 and 6 h after exposure, the activity of lipoprotein lipase decreased in adipose tissue and increased in heart muscle of the irradiated fed rats; in fasting rats it decreased in heart muscle at 1 h after exposure. The concentration of serum triglycerides increased at 1 h and decreased at 6 h after exposure in fed rats. In these rats, alterations in serum triglycerides correlated with changes in lipoprotein lipase activity in adipose tissue. Alterations observed at the later time periods were more dependent on the time interval between irradiation and the analysis. Lipoprotein lipase activity increased with time after irradiation up to the maximal values at 72 h. Fasting prior to and after irradiation substantially modified the response of animals to radiation. (author)

  6. High-throughput virtual screening with e-pharmacophore and molecular simulations study in the designing of pancreatic lipase inhibitors

    OpenAIRE

    Veeramachaneni GK; Raj KK; Chalasani LM; JS, Bondili; Talluri VR

    2015-01-01

    Ganesh Kumar Veeramachaneni, K Kranthi Raj, Leela Madhuri Chalasani, Jayakumar Singh Bondili, Venkateswara Rao Talluri Department of Biotechnology, K L University, Guntur, India Background: Obesity is a progressive metabolic disorder in the current world population, and is characterized by the excess deposition of fat in the adipose tissue. Pancreatic lipase is one of the key enzymes in the hydrolysis of triglycerides into monoglycerides and free fatty acids, and is thus considered a promis...

  7. Selective Synthesis of Human Milk Fat-Style Structured Triglycerides from Microalgal Oil in a Microfluidic Reactor Packed with Immobilized Lipase

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jun; Liu, Xi; Wang, Xu-Dong; Dong, Tao; Zhao, Xing-Yu; Zhu, Dan; Mei, Yi-Yuan; Wu, Guo-Hua

    2016-11-01

    Human milk fat-style structured triacylglycerols were produced from microalgal oil in a continuous microfluidic reactor packed with immobilized lipase for the first time. A remarkably high conversion efficiency was demonstrated in the microreactor with reaction time being reduced by 8 times, Michaelis constant decreased 10 times, the lipase reuse times increased 2.25-fold compared to those in a batch reactor. In addition, the content of palmitic acid at sn-2 position (89.0%) and polyunsaturated fatty acids at sn-1, 3 positions (81.3%) are slightly improved compared to the product in a batch reactor. The increase of melting points (1.7 degrees C) and decrease of crystallizing point (3 degrees C) implied higher quality product was produced using the microfluidic technology. The main cost can be reduced from $212.3 to $14.6 per batch with the microreactor. Overall, the microfluidic bioconversion technology is promising for modified functional lipids production allowing for cost-effective approach to produce high-value microalgal coproducts.

  8. Selective synthesis of human milk fat-style structured triglycerides from microalgal oil in a microfluidic reactor packed with immobilized lipase.

    Science.gov (United States)

    Wang, Jun; Liu, Xi; Wang, Xu-Dong; Dong, Tao; Zhao, Xing-Yu; Zhu, Dan; Mei, Yi-Yuan; Wu, Guo-Hua

    2016-11-01

    Human milk fat-style structured triacylglycerols were produced from microalgal oil in a continuous microfluidic reactor packed with immobilized lipase for the first time. A remarkably high conversion efficiency was demonstrated in the microreactor with reaction time being reduced by 8 times, Michaelis constant decreased 10 times, the lipase reuse times increased 2.25-fold compared to those in a batch reactor. In addition, the content of palmitic acid at sn-2 position (89.0%) and polyunsaturated fatty acids at sn-1, 3 positions (81.3%) are slightly improved compared to the product in a batch reactor. The increase of melting points (1.7°C) and decrease of crystallizing point (3°C) implied higher quality product was produced using the microfluidic technology. The main cost can be reduced from $212.3 to $14.6 per batch with the microreactor. Overall, the microfluidic bioconversion technology is promising for modified functional lipids production allowing for cost-effective approach to produce high-value microalgal coproducts.

  9. Selective synthesis of human milk fat-style structured triglycerides from microalgal oil in a microfluidic reactor packed with immobilized lipase.

    Science.gov (United States)

    Wang, Jun; Liu, Xi; Wang, Xu-Dong; Dong, Tao; Zhao, Xing-Yu; Zhu, Dan; Mei, Yi-Yuan; Wu, Guo-Hua

    2016-11-01

    Human milk fat-style structured triacylglycerols were produced from microalgal oil in a continuous microfluidic reactor packed with immobilized lipase for the first time. A remarkably high conversion efficiency was demonstrated in the microreactor with reaction time being reduced by 8 times, Michaelis constant decreased 10 times, the lipase reuse times increased 2.25-fold compared to those in a batch reactor. In addition, the content of palmitic acid at sn-2 position (89.0%) and polyunsaturated fatty acids at sn-1, 3 positions (81.3%) are slightly improved compared to the product in a batch reactor. The increase of melting points (1.7°C) and decrease of crystallizing point (3°C) implied higher quality product was produced using the microfluidic technology. The main cost can be reduced from $212.3 to $14.6 per batch with the microreactor. Overall, the microfluidic bioconversion technology is promising for modified functional lipids production allowing for cost-effective approach to produce high-value microalgal coproducts. PMID:27566521

  10. Piromelatine decreases triglyceride accumulation in insulin resistant 3T3-L1 adipocytes: role of ATGL and HSL.

    Science.gov (United States)

    Wang, Ping-Ping; She, Mei-Hua; He, Ping-Ping; Chen, Wu-Jun; Laudon, Moshe; Xu, Xuan-Xuan; Yin, Wei-Dong

    2013-08-01

    Piromelatine, a novel investigational multimodal sleep medicine, is developed for the treatment of patients with primary and co-morbid insomnia. Piromelatine has been shown to inhibit weight gain and improve insulin sensitivity in high-fat/high-sucrose-fed (HFHS) rats. Considering that piromelatine has also been implicated in lowering of triglyceride levels in HFHS rats, this work elucidated whether this effect involves in the regulation of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) in triglyceride (TG) metabolism. In this study, we investigated the effects of piromelatine and MT2 receptors inhibition on TG content, insulin-stimulated glucose uptake, and the expressions of ATGL and HSL in 3T3-L1 adipocytes preincubated in high glucose and high insulin (HGI) conditions. Our results showed that culturing 3T3-L1 adipocytes under HGI conditions increased triglyceride accumulation with concomitant decrease of ATGL and HSL expression, inducing insulin resistance in 3T3-L1 adipocytes. We also found that triglyceride accumulation was significantly inhibited and the levels of ATGL/HSL increased after melatonin or piromelatine treatment. The effects of melatonin/piromelatine (10 nM) were counteracted by pretreatment with the relatively selective MT2 receptor antagonist luzindole (100 nM). In this study, our data demonstrate that piromelatine reverses high glucose and high insulin-induced triglyceride accumulation in 3T3-L1 adipocytes, possibly through up-regulating of ATGL and HSL expression via a melatonin-dependent manner.

  11. Reduced lipolysis response to adipose afferent reflex involved in impaired activation of adrenoceptor-cAMP-PKA-hormone sensitive lipase pathway in obesity

    Science.gov (United States)

    Ding, Lei; Zhang, Feng; Zhao, Ming-Xia; Ren, Xing-Sheng; Chen, Qi; Li, Yue-Hua; Kang, Yu-Ming; Zhu, Guo-Qing

    2016-01-01

    Chemical stimulation of white adipose tissue (WAT) causes adipose afferent reflex (AAR) and sympathetic activation. This study is to investigate the effects of AAR on lipolysis and the mechanisms of attenuated lipolysis response to enhanced AAR in obesity. Obesity was caused by high-fat diet for 12 weeks in rats. AAR was induced by injection of capsaicin into inguinal WAT or electrical stimulation of epididymal WAT afferent nerve. AAR caused sympathetic activation, which was enhanced in obesity rats. AAR increased cAMP levels and PKA activity, promoted hormone sensitive lipase (HSL) and perilipin phosphorylation, and increased lipolysis in WAT, which were attenuated in obesity rats. PKA activity, cAMP, perilipin and β-adrenoceptor levels were reduced, while HSL was upregulated in adipocytes from obesity rats. In primary adipocytes, isoproterenol increased cAMP levels and PKA activity, promoted HSL and perilipin phosphorylation, and increased lipolysis, which were attenuated in obesity rats. The attenuated effects of isoproterenol in adipocytes from obesity rats were prevented by a cAMP analogue dbcAMP. The results indicate that reduced lipolysis response to enhanced AAR in obesity is attributed to the impaired activation of β-adrenoceptor-cAMP-PKA-HSL pathway. Increased cAMP level in adipocytes rectifies the attenuated lipolysis in obesity. PMID:27694818

  12. Increased Oxidative Stress Impairs Adipose Tissue Function in Sphingomyelin Synthase 1 Null Mice

    OpenAIRE

    Masato Yano; Tadashi Yamamoto; Naotaka Nishimura; Tomomi Gotoh; Ken Watanabe; Kazutaka Ikeda; Yohei Garan; Ryo Taguchi; Koichi Node; Toshiro Okazaki; Yuichi Oike

    2013-01-01

    Sphingomyelin synthase 1 (SMS1) catalyzes the conversion of ceramide to sphingomyelin. Here, we found that SMS1 null mice showed lipodystrophic phenotype. Mutant mice showed up-regulation of plasma triglyceride concentrations accompanied by reduction of white adipose tissue (WAT) as they aged. Lipoprotein lipase (LPL) activity was severely reduced in mutant mice. In vivo analysis indicated that fatty acid uptake in WAT but not in liver decreased in SMS1 null compared to wild-type mice. In vit...

  13. Hormone-sensitive lipase (HSL) expression and regulation in skeletal muscle

    DEFF Research Database (Denmark)

    Langfort, J; Ploug, T; Ihlemann, J;

    1998-01-01

    Because the enzymatic regulation of muscle triglyceride metabolism is poorly understood we explored the character and activation of neutral lipase in muscle. Western blotting of isolated rat muscle fibers demonstrated expression of hormone-sensitive lipase (HSL). In incubated soleus muscle...... epinephrine increased neutral lipase activity by beta-adrenergic mechanisms involving cyclic AMP-dependent protein kinase (PKA). The increase was paralleled by an increase in glycogen phosphorylase activity and could be abolished by antiserum against HSL. Electrical stimulation caused a transient increase...... studies have shown that HSL is present in skeletal muscle cells and is stimulated in parallel with glycogen phosphorylase by both epinephrine and contractions. HSL adapts differently to training in muscle compared with adipose tissue....

  14. Characterization of lipase activities in obese Pima indians. Decreases with weight reduction.

    OpenAIRE

    Reitman, J S; Kosmakos, F C; Howard, B V; Taskinen, M R; Kuusi, T.; Nikkila, E A

    1982-01-01

    Adipose tissue and muscle lipoprotein lipase and postheparin hepatic and lipoprotein lipase activities have been measured in a group of 21 Pima Indian males over a wide range of body weight to determine the relationship between obesity and these lipase activities. There was a significant positive correlation between adipose tissue lipoprotein lipase and obesity; muscle and postheparin lipoprotein lipase and hepatic lipase were not related to degree of obesity. Fasting insulin levels were not ...

  15. Phospholipase C-related catalytically inactive protein (PRIP regulates lipolysis in adipose tissue by modulating the phosphorylation of hormone-sensitive lipase.

    Directory of Open Access Journals (Sweden)

    Toshiya Okumura

    Full Text Available Phosphorylation of hormone-sensitive lipase (HSL and perilipin by protein kinase A (PKA promotes the hydrolysis of lipids in adipocytes. Although activation of lipolysis by PKA has been well studied, inactivation via protein phosphatases is poorly understood. Here, we investigated whether phospholipase C-related catalytically inactive protein (PRIP, a binding partner for protein phosphatase 1 and protein phosphatase 2A (PP2A, is involved in lipolysis by regulating phosphatase activity. PRIP knockout (PRIP-KO mice displayed reduced body-fat mass as compared with wild-type mice fed with standard chow ad libitum. Most other organs appeared normal, suggesting that mutant mice had aberrant fat metabolism in adipocytes. HSL in PRIP-KO adipose tissue was highly phosphorylated compared to that in wild-type mice. Starvation of wild-type mice or stimulation of adipose tissue explants with the catabolic hormone, adrenaline, translocated both PRIP and PP2A from the cytosol to lipid droplets, but the translocation of PP2A was significantly reduced in PRIP-KO adipocytes. Consistently, the phosphatase activity associated with lipid droplet fraction in PRIP-KO adipocytes was significantly reduced and was independent of adrenaline stimulation. Lipolysis activity, as assessed by measurement of non-esterified fatty acids and glycerol, was higher in PRIP-KO adipocytes. When wild-type adipocytes were treated with a phosphatase inhibitor, they showed a high lipolysis activity at the similar level to PRIP-KO adipocytes. Collectively, these results suggest that PRIP promotes the translocation of phosphatases to lipid droplets to trigger the dephosphorylation of HSL and perilipin A, thus reducing PKA-mediated lipolysis.

  16. Effects of 2 G on adiposity, leptin, lipoprotein lipase, and uncoupling protein-1 in lean and obese Zucker rats

    Science.gov (United States)

    Warren, L. E.; Horwitz, B. A.; Hamilton, J. S.; Fuller, C. A.

    2001-01-01

    Male Zucker rats were exposed to 2 G for 8 wk to test the hypothesis that the leptin regulatory pathway contributes to recovery from effects of 2 G on feeding, growth, and nutrient partitioning. After initial hypophagia, body mass-independent food intake of the lean rats exposed to 2 G surpassed that of the lean rats maintained at 1 G, but food intake of the obese rats exposed to 2 G remained low. After 8 wk at 2 G, body mass and carcass fat were less in both genotypes. Leptin and percent fat were lower in lean rats exposed to 2 G vs. 1 G but did not differ in obese rats exposed to 2 G vs. 1 G. Although exposure to 2 G did not alter uncoupling protein-1 levels, it did elicit white fat pad-specific changes in lipoprotein lipase activity in obese but not lean rats. We conclude that 2 G affects both genotypes but that the lean Zucker rats recover their food intake and growth rate and retain "normal" lipoprotein lipase activity to a greater degree than do the obese rats, emphasizing the importance of a functional leptin regulatory pathway in this acclimation.

  17. Triglyceride level

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003493.htm Triglyceride level To use the sharing features on this page, ... and Metabolism; Council on Arteriosclerosis, Thrombosis and Vascular Biology; Council on Cardiovascular Nursing; Council on the Kidney ...

  18. Developmental regulation of adipose tissue growth through hyperplasia and hypertrophy in the embryonic Leghorn and broiler.

    Science.gov (United States)

    Chen, Paula; Suh, Yeunsu; Choi, Young Min; Shin, Sangsu; Lee, Kichoon

    2014-07-01

    The United States is a world leader in poultry production, which is the reason why achieving better performance and muscle growth each year is a necessity. Reducing accretion of adipose tissue is another important factor for poultry producers because this allows more nutrients to be directed toward muscle growth, but the effect of embryonic adipose growth on posthatch development has not been fully understood. The purpose of this study was to investigate the total DNA mass, morphological characteristics, differentiation markers, and triglyceride breakdown factors of embryonic adipose tissue, and their relation to hyperplastic and hypertrophic growth within layers (Leghorn) and meat-type chickens (broilers). After embryonic day (E) 12, broiler weight was significantly higher than Leghorn, and this trend continued throughout the rest of incubation and posthatch (P Adipose triglyceride lipase was highly expressed at E20 and d 1 posthatch to mobilize triglyceride degradation for energy during hatching. Thus, embryonic chicken adipose tissue was found to develop by hyperplastic mechanisms followed by hypertrophy. At embryonic stages and early posthatch, layer- and meat-type chicken adipose growth does not differ, which suggests breed differences occur posthatch.

  19. Comparative analyses of lipoprotein lipase, hepatic lipase, and endothelial lipase, and their binding properties with known inhibitors.

    Directory of Open Access Journals (Sweden)

    Ziyun Wang

    Full Text Available The triglyceride lipase gene subfamily plays a central role in lipid and lipoprotein metabolism. There are three members of this subfamily: lipoprotein lipase, hepatic lipase, and endothelial lipase. Although these lipases are implicated in the pathophysiology of hyperlipidemia and atherosclerosis, their structures have not been fully solved. In the current study, we established homology models of these three lipases, and carried out analysis of their activity sites. In addition, we investigated the kinetic characteristics for the catalytic residues using a molecular dynamics simulation strategy. To elucidate the molecular interactions and determine potential key residues involved in the binding to lipase inhibitors, we analyzed the binding pockets and binding poses of known inhibitors of the three lipases. We identified the spatial consensus catalytic triad "Ser-Asp-His", a characteristic motif in all three lipases. Furthermore, we found that the spatial characteristics of the binding pockets of the lipase molecules play a key role in ligand recognition, binding poses, and affinities. To the best of our knowledge, this is the first report that systematically builds homology models of all the triglyceride lipase gene subfamily members. Our data provide novel insights into the molecular structures of lipases and their structure-function relationship, and thus provides groundwork for functional probe design towards lipase-based therapeutic inhibitors for the treatment of hyperlipidemia and atherosclerosis.

  20. Agonists of the G protein-coupled receptor 109A-mediated pathway promote antilipolysis by reducing serine residue 563 phosphorylation of hormone-sensitive lipase in bovine adipose tissue explants.

    Science.gov (United States)

    Kenéz, A; Locher, L; Rehage, J; Dänicke, S; Huber, K

    2014-01-01

    A balanced lipolytic regulation in adipose tissues based on fine-tuning of prolipolytic and antilipolytic pathways is of vital importance to maintain the metabolic health in dairy cows. Antilipolytic pathways, such as the G protein-coupled receptor 109A (GPR109A)-mediated pathway and the insulin signaling pathway in bovine adipose tissues may be involved in prohibiting excessive lipomobilization by reducing triglycerol hydrolysis. This study aimed to evaluate the in vitro antilipolytic potential of the mentioned pathways in bovine adipose tissue explants. Therefore, subcutaneous and retroperitoneal adipose tissue samples (approximately 100mg) of German Holstein cows were treated for 90 min ex vivo with nicotinic acid (2, 8, or 32 μM), nicotinamide (2, 8, or 32 μM), β-hydroxybutyrate (0.2, 1, or 5mM), or insulin (12 mU/L), with a concurrent lipolytic challenge provoked with 1 μM isoproterenol. Lipolytic and antilipolytic responses of the adipose tissues were assessed by measuring free glycerol and nonesterified fatty acid release. To identify molecular components of the investigated antilipolytic pathways, protein abundance of GPR109A and the extent of hormone-sensitive lipase (HSL) phosphorylation at serine residue 563 were detected by Western blotting. Treatment with nicotinic acid or β-hydroxybutyrate decreased the lipolytic response in adipose tissue explants and concurrently reduced the extent of HSL phosphorylation, but treatment with nicotinamide or insulin did not. Subcutaneous adipose tissue constitutively expressed more GPR109A protein, but no other depot-specific differences were observed. This study provides evidence that the GPR109A-mediated pathway is functionally existent in bovine adipose tissues, and confirms that HSL phosphorylation at serine residue 563 is also important in antilipolytic regulation in vitro. This antilipolytic pathway may be involved in a balanced lipid mobilization in the dairy cow.

  1. Hypoxia-induced mobilization of stored triglycerides in the euryoxic goby Gillichthys mirabilis.

    Science.gov (United States)

    Gracey, Andrew Y; Lee, Tsung-Han; Higashi, Richard M; Fan, Teresa

    2011-09-15

    Environmental hypoxia is a common challenge that many aquatic organisms experience in their habitat. Responding to hypoxia requires metabolic reprogramming so that energy-demanding processes are regulated to match available energy reserves. In this study we explored the transcriptional control of metabolic reorganization in the liver of a hypoxia-tolerant burrow-dwelling goby, Gillichthys mirabilis. Gene expression data revealed that pathways associated with triglyceride hydrolysis were upregulated by hypoxia whereas pathways associated with triglyceride synthesis were downregulated. This finding was supported by tissue histology, which showed that the size of hepatic lipid droplets declined visibly during exposure to hypoxia. Proton nuclear magnetic resonance analysis confirmed the mobilization of hepatic triglycerides, which declined 2.7-fold after 5 days of hypoxia. The enzyme, adipose triglyceride lipase, was implicated in the mobilization of triglycerides because its expression increased at the level of both transcript and protein. This observation raises questions regarding the regulation of fat metabolism during hypoxia and the role played by the hypoxia-responsive gene leptin.

  2. Overview of fungal lipase: a review.

    Science.gov (United States)

    Singh, Abhishek Kumar; Mukhopadhyay, Mausumi

    2012-01-01

    Lipases (triacylglycerolacyl hydrolases, EC3.1.1.3) are class of enzymes which catalyze the hydrolysis of long-chain triglycerides. In this review paper, an overview regarding the fungal lipase production, purification, and application is discussed. The review describes various industrial applications of lipase in pulp and paper, food, detergent, and textile industries. Some important lipase-producing fungal genera include Aspergillus, Penicillium, Rhizopus, Candida, etc. Current fermentation process techniques such as batch, fed-batch, and continuous mode of lipase production in submerged and solid-state fermentations are discussed in details. The purification of lipase by hydrophobic interaction chromatography is also discussed. The development of mathematical models applied to lipase production is discussed with special emphasis on lipase engineering. PMID:22072143

  3. 脂肪细胞三酰甘油分解代谢相关调节的研究进展%Research progress in regulation of triglyceride hydrolysis in adipocytes

    Institute of Scientific and Technical Information of China (English)

    黄文钰

    2013-01-01

    Adipose tissue is an important station for energy storage and service in the body.The dysregulation of triglyceride hydrolysis is related to obesity and other lipid metabolism disorders.Hormone-sensitive lipase (HSL) and adipose triacylglycerol lipase(ATGL) are major enzymes for triglyceride hydrolysis.Perilipin is an important regulatory factor for lipolysis.This review summarized advance in research on the main regulatory pathway for triglyceride hydrolysis and the roles of HSL,ATGL,and perilipin in triglyceride hydrolysis in adipocytes.%脂肪组织是体内重要的能量储存和供应站,脂肪细胞中的三酰甘油分解代谢紊乱与肥胖等代谢疾病密切相关.在多种脂肪分解途径中,有许多机制尚未明确.已知激素敏感性脂肪酶、脂肪三酰甘油脂肪酶是重要的脂肪细胞三酰甘油水解酶,围脂滴蛋白是脂肪分解的重要调节因子.本综述将着重介绍脂肪细胞三酰甘油分解代谢的主要调节通路和上述酶及蛋白作用机制方面的研究进展.

  4. Pancreatic Lipase-related Protein 2 Is the Major Colipase-Dependent Pancreatic Lipase in Suckling Mice1

    OpenAIRE

    D’Agostino, Dymphna; Lowe, Mark E.

    2004-01-01

    Suckling mice express colipase before the expression of pancreatic triglyceride lipase. Yet, efficient fat digestion in newborns requires colipase, suggesting that colipase may act as a cofactor for another lipase such as pancreatic lipase-related protein 2 (PLRP2). We determined whether PLRP2 or another lipase depends on colipase for maximal activity in newborn mice by analyzing extracts from the pancreas of 4-d-old colipase-deficient and PLRP2-deficient mice. Pancreatic extracts from colipa...

  5. Leu452His mutation in lipoprotein lipase gene transfer associated with hypertriglyceridemia in mice in vivo.

    Directory of Open Access Journals (Sweden)

    Kaiyue Sun

    Full Text Available Mutated mouse lipoprotein lipase (LPL containing a leucine (L to histidine (H substitution at position 452 was transferred into mouse liver by hydrodynamics-based gene delivery (HD. Mutated-LPL (MLPL gene transfer significantly increased the concentrations of plasma MLPL and triglyceride (TG but significantly decreased the activity of plasma LPL. Moreover, the gene transfer caused adiposis hepatica and significantly increased TG content in mouse liver. To understand the effects of MLPL gene transfer on energy metabolism, we investigated the expression of key functional genes related to energy metabolism in the liver, epididymal fat, and leg muscles. The mRNA contents of hormone-sensitive lipase (HSL, adipose triglyceride lipase (ATGL, fatty acid-binding protein (FABP, and uncoupling protein (UCP were found to be significantly reduced. Furthermore, we investigated the mechanism by which MLPL gene transfer affected fat deposition in the liver, fat tissue, and muscle. The gene expression and protein levels of forkhead Box O3 (FOXO3, AMP-activated protein kinase (AMPK, and peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC-1α were found to be remarkably decreased in the liver, fat and muscle. These results suggest that the Leu452His mutation caused LPL dysfunction and gene transfer of MLPL in vivo produced resistance to the AMPK/PGC-1α signaling pathway in mice.

  6. Lipase Test

    Science.gov (United States)

    ... be limited. Home Visit Global Sites Search Help? Lipase Share this page: Was this page helpful? Also known as: LPS Formal name: Lipase Related tests: Amylase , Trypsin , Trypsinogen At a Glance ...

  7. Resistin in dairy cows: plasma concentrations during early lactation, expression and potential role in adipose tissue.

    Directory of Open Access Journals (Sweden)

    Maxime Reverchon

    Full Text Available Resistin is an adipokine that has been implicated in energy metabolism regulation in rodents but has been little studied in dairy cows. We determined plasma resistin concentrations in early lactation in dairy cows and investigated the levels of resistin mRNA and protein in adipose tissue and the phosphorylation of several components of insulin signaling pathways one week post partum (1 WPP and at five months of gestation (5 MG. We detected resistin in mature bovine adipocytes and investigated the effect of recombinant bovine resistin on lipolysis in bovine adipose tissue explants. ELISA showed that plasma resistin concentration was low before calving, subsequently increasing and reaching a peak at 1 WPP, decreasing steadily thereafter to reach pre-calving levels at 6 WPP. Plasma resistin concentration was significantly positively correlated with plasma non esterified fatty acid (NEFA levels and negatively with milk yield, dry matter intake and energy balance between WPP1 to WPP22. We showed, by quantitative RT-PCR and western blotting, that resistin mRNA and protein levels in adipose tissue were higher at WPP1 than at 5 MG. The level of phosphorylation of several early and downstream insulin signaling components (IRβ, IRS-1, IRS-2, Akt, MAPK ERK1/2, P70S6K and S6 in adipose tissue was also lower at 1 WPP than at 5 MG. Finally, we showed that recombinant bovine resistin increased the release of glycerol and mRNA levels for ATGL (adipose triglyceride lipase and HSL (hormone-sensitive lipase in adipose tissue explants. Overall, resistin levels were high in the plasma and adipose tissue and were positively correlated with NEFA levels after calving. Resistin is expressed in bovine mature adipocytes and promotes lipid mobilization in adipose explants in vitro.

  8. Pronounced expression of the lipolytic inhibitor G0/G1 Switch Gene 2 (G0S2) in adipose tissue from brown bears (Ursus arctos) prior to hibernation

    DEFF Research Database (Denmark)

    Jessen, Niels; Nielsen, Thomas S; Vendelbo, Mikkel H;

    2016-01-01

    gaining weight may therefore provide novel insight toward the development of human therapies. Blood and subcutaneous adipose tissue were collected from immobilized free-ranging brown bears (fitted with GPS-collars) during hibernation in winter and from the same bears during the active period in summer...... in Dalarna, Sweden. The expression of lipid droplet-associated proteins in adipose tissue was examined under the hypothesis that bears suppress lipolysis during summer while gaining weight by increased expression of negative regulators of lipolysis. Adipose triglyceride lipase (ATGL) expression did...... increased during summer. Free-ranging brown bears display potent upregulation of inhibitors of lipolysis in adipose tissue during summer. This is a potential mechanism for increased insulin sensitivity during weight gain and G0S2 may serve as a target to modulate insulin sensitivity....

  9. GPIHBP1 and Plasma Triglyceride Metabolism

    DEFF Research Database (Denmark)

    Fong, Loren G; Young, Stephen G; Beigneux, Anne P;

    2016-01-01

    GPIHBP1, a GPI-anchored protein in capillary endothelial cells, is crucial for the lipolytic processing of triglyceride-rich lipoproteins (TRLs). GPIHBP1 shuttles lipoprotein lipase (LPL) to its site of action in the capillary lumen and is essential for the margination of TRLs along capillaries...... of the protein and abolish its capacity to bind and transport LPL. The discovery of GPIHBP1 has substantially revised our understanding of intravascular triglyceride metabolism but has also raised many new questions for future research....

  10. Lipase Induction in Mucor hiemalis

    OpenAIRE

    Akhtar, M. Waheed; Mirza, A. Q.; Chughtai, M. I. D.

    1980-01-01

    The influence on lipase induction in Mucor hiemalis of different types of triglycerides containing mainly oleic acid (olive oil), erucic acid (mustard oil), or saturated fatty acids of 8 to 16 carbons (coconut oil) was studied. The fungus was grown in shake flasks in a fermentation medium containing peptone, minerals, and glucose or one of the oils as the carbon source. Maximum lipase was produced when the initial pH of the fermentation medium was kept at 4.0. Addition of Ca2+ to the medium d...

  11. Pancreatic lipase-related protein 2 digests fats in human milk and formula in concert with gastric lipase and carboxyl ester lipase

    OpenAIRE

    Johnson, Karin; Ross, Leah; Miller, Rita; Xiao, Xunjun; Lowe, Mark E.

    2013-01-01

    INTRODUCTION Dietary fats must be digested into fatty acids and monoacylglycerols prior to absorption. In adults, colipase-dependent pancreatic triglyceride lipase (PTL) contributes significantly to fat digestion. In newborn rodents and humans, the pancreas expresses low levels of PTL. In rodents, a homologue of PTL, pancreatic lipase related protein 2 (PLRP2) and carboxyl ester lipase (CEL) compensate for the lack of PTL. In human newborns, the role for PLRP2 in dietary fat digestion is uncl...

  12. Hydrolysis of human milk fat globules by pancreatic lipase: role of colipase, phospholipase A2, and bile salts.

    OpenAIRE

    Bläckberg, L; Hernell, O.; Olivecrona, T

    1981-01-01

    Human milk fat globules were used to explore how dietary triglycerides are hydrolyzed by pancreatic lipase. These triglycerides were hydrolyzed very slowly by lipase alone as if the surface layer of proteins and phospholipids impeded the action of the enzyme. The inhibition of lipase activity could be overcome by addition either of colipase or of pancreatic phospholipase A2. Colipase enhanced triglyceride hydrolysis in a dose-dependent manner whether bile salts were present or not. Bile salts...

  13. Regulation of G0/G1 switch gene 2 (G0S2) expression in human adipose tissue.

    Science.gov (United States)

    Skopp, Alexander; May, Marcus; Janke, Juergen; Kielstein, Heike; Wunder, Ruth; Flade-Kuthe, Ricarda; Kuthe, Andreas; Jordan, Jens; Engeli, Stefan

    2016-05-01

    The G0/G1 switch gene 2 (G0S2) protein attenuated adipose triglyceride lipase (ATGL) activity and decreased lipolysis in rodent and human adipocytes. We hypothesized that G0S2 mRNA expression in human adipose tissue is influenced by depot, adipocyte size, body weight and caloric intake. Adipose tissue samples were obtained during abdominal surgery and by needle biopsy before and 3 h after an extended glucose load in lean subjects. G0S2 mRNA was 7× higher expressed in mature human adipocytes compared to the stromavascular fraction. Cell size inversely correlated with G0S2 mRNA expression in both, subcutaneous and omental adipose depots. G0S2 mRNA expression was 75% higher in subcutaneous compared to omental adipose tissue. Obesity was associated with lower G0S2 mRNA expression in subcutaneous adipose tissue. Acute glucose ingestion after an overnight fast did not significantly increase G0S2 expression in subcutaneous adipose tissue. In conclusion, differences in G0S2 expression may explain depot-specific and obesity-associated differences in lipolysis on the molecular level. PMID:26707160

  14. Increasing insulin resistance accentuates the effect of triglyceride-associated loci on serum triglycerides during five years

    DEFF Research Database (Denmark)

    Justesen, Johanne M; Andersson, Ehm A; Allin, Kristine H;

    2016-01-01

    Blood concentrations of triglycerides are influenced by genetic factors, as well as a number of environmental factors including adiposity and glucose homeostasis. The aim to investigate the association between a weighted serum triglyceride genetic risk score (wGRS) and changes in fasting serum...... triglyceride level over five years and to test whether the effect of the wGRS was modified by 5-year changes of adiposity, insulin resistance and lifestyle factors. A total of 3,474 non-diabetic individuals from the Danish Inter99 cohort participated in both the baseline and 5-year follow-up physical...... examinations and had information on the wGRS comprising 39 genetic variants. In a linear regression model adjusted for age, sex and baseline serum triglyceride, the wGRS was associated with increased serum triglyceride levels over 5 years (per allele effect=1.3% (1.0;1.6); P=1.0*10(-17)). This triglyceride...

  15. Bacterial lipases

    NARCIS (Netherlands)

    Jaeger, Karl-Erich; Ransac, Stéphane; Dijkstra, Bauke W.; Colson, Charles; Heuvel, Margreet van; Misset, Onno

    1994-01-01

    Many different bacterial species produce lipases which hydrolyze esters of glycerol with preferably long-chain fatty acids. They act at the interface generated by a hydrophobic lipid substrate in a hydrophilic aqueous medium. A characteristic property of lipases is called interfacial activation, mea

  16. Lipases in Medicine: An Overview.

    Science.gov (United States)

    Loli, Heni; Narwal, Sunil Kumar; Saun, Nitin Kumar; Gupta, Reena

    2015-01-01

    Lipases are part of the family of hydrolases that act on carboxylic ester bonds. They are involved in catalyzing the hydrolysis of triglycerides (TG) into chylomicrons and very low density lipoprotein (VLDL) particles. Uses of lipases are evolving rapidly and currently they are reported to show high potential in medicine. Intensive study and investigations have led researchers to explore lipases for their use in substitution therapy, where in enzyme deficiency during diseased conditions is compensated by their external administration. In our body, they are used to break down fats present in food so that they can be absorbed in the intestine and deficiency of lipases leads to malabsorption of fats and fat-soluble vitamins. Lipases help a person who has cystic fibrosis, Alzheimer's disease, atherosclerosis and act as a candidate target for cancer prevention and therapy. They act as diagnostic tool and their presence or increasing levels can indicate certain infection or disease. Obesity causes metabolic disease and is a serious health problem around the world. Thus inhibiting digestive lipase to reduce fat absorption has become the main pharmacological approach to the treatment of obesity in recent years. PMID:26156413

  17. Serum pancreatic lipase as a screening test for cystic fibrosis.

    OpenAIRE

    Adriaenssens, K; Van Riel, L

    1982-01-01

    Pancreatic lipase catalyses the hydrolysis of emulsified triglycerides to form a transparent solution of monoglycerides and fatty acids. Levels of serum pancreatic lipase were measured in neonates known to have cystic fibrosis and compared with levels in control infants. During the first weeks of life infants with cystic fibrosis had raised serum pancreatic lipase values in parallel with raised serum trypsin values. A simple and specific turbidimetric dried blood spot assay for serum pancreat...

  18. I. Lipid metabolism stimulated by altered intracellular calcium in cultured fibroblasts. II. Regulation of the activity of rat adipose tissue lipoprotein lipase

    International Nuclear Information System (INIS)

    The cell killing process of 3T3 Swiss mouse fibroblasts stimulated by Ca2+ plus A23187, a Ca2+ ionophore has been studied. The aim of this research is to understand the biochemical mechanism of this process, i.e, to elucidate the step involved and to characterize the enzymes involved with each steps in the lipid metabolism stimulated in cultured fibroblasts undergoing a toxic death response. Parallel 3T3 cultures biosynthetically labeled with lipid precursors were examined under Ca2+-mediated killing conditions. Labeled lipids were extracted and analyzed by thin-layer chromatography and autoradiography. Evidence for activation of a phosphatidylinositol-specific phospholipase C has been obtained in injured 3T3 cells labeled with [3H]glycerol and [3H]inositol. To simplify the system for studying the lipoprotein lipase reaction, our laboratory prepared the chromophore containing a substrate: 1,2-dipalmitoyl-3-β-2-furylacryloyltriacylglycerol (DPFATG). By using this artificial lipid we could readily investigate the lipoprotein lipase reactions, since the absorbance change directly represents the hydrolysis of the chromophoric side chain of the substrate

  19. Tofogliflozin Improves Insulin Resistance in Skeletal Muscle and Accelerates Lipolysis in Adipose Tissue in Male Mice.

    Science.gov (United States)

    Obata, Atsushi; Kubota, Naoto; Kubota, Tetsuya; Iwamoto, Masahiko; Sato, Hiroyuki; Sakurai, Yoshitaka; Takamoto, Iseki; Katsuyama, Hisayuki; Suzuki, Yoshiyuki; Fukazawa, Masanori; Ikeda, Sachiya; Iwayama, Kaito; Tokuyama, Kumpei; Ueki, Kohjiro; Kadowaki, Takashi

    2016-03-01

    Sodium glucose cotransporter 2 inhibitors have attracted attention as they exert antidiabetic and antiobesity effects. In this study, we investigated the effects of tofogliflozin on glucose homeostasis and its metabolic consequences and clarified the underlying molecular mechanisms. C57BL/6 mice were fed normal chow containing tofogliflozin (0.005%) for 20 weeks or a high-fat diet containing tofogliflozin (0.005%) for 8 weeks ad libitum. In addition, the animals were pair-fed in relation to controls to exclude the influence of increased food intake. Tofogliflozin reduced the body weight gain, mainly because of fat mass reduction associated with a diminished adipocyte size. Glucose tolerance and insulin sensitivity were ameliorated. The serum levels of nonesterified fatty acid and ketone bodies were increased and the respiratory quotient was decreased in the tofogliflozin-treated mice, suggesting the acceleration of lipolysis in the white adipose tissue and hepatic β-oxidation. In fact, the phosphorylation of hormone-sensitive lipase and the adipose triglyceride lipase protein levels in the white adipose tissue as well as the gene expressions related to β-oxidation, such as Cpt1α in the liver, were significantly increased. The hepatic triglyceride contents and the expression levels of lipogenic genes were decreased. Pair-fed mice exhibited almost the same results as mice fed an high-fat diet ad libitum. Moreover, a hyperinsulinemic-euglycemic clamp revealed that tofogliflozin improved insulin resistance by increasing glucose uptake, especially in the skeletal muscle, in pair-fed mice. Taken together, these results suggest tofogliflozin ameliorates insulin resistance and obesity by increasing glucose uptake in skeletal muscle and lipolysis in adipose tissue. PMID:26713783

  20. Fat-reducing effects of dehydroepiandrosterone involve upregulation of ATGL and HSL expression, and stimulation of lipolysis in adipose tissue.

    Science.gov (United States)

    Karbowska, Joanna; Kochan, Zdzislaw

    2012-11-01

    Dehydroepiandrosterone (DHEA) reduces body fat in rodents and humans, and increases glycerol release from isolated rat epididymal adipocytes and human visceral adipose tissue explants. It suggests that DHEA stimulates triglyceride hydrolysis in adipose tissue; however, the mechanisms underlying this action are still unclear. We examined the effects of DHEA on the expression of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL), the key enzymes of lipolysis, in rat epididymal white adipose tissue (eWAT). Male Wistar rats were fed a diet containing 0.6% DHEA for 2 weeks and eWAT was analyzed for mRNA and protein expression of ATGL and HSL, as well as mRNA expression of peroxisome proliferator-activated receptor γ 2 (PPARγ2) and its downstream target fatty acid translocase (FAT). Glycerol release from eWAT explants and serum free fatty acids (FFA) were also measured. Rats that received DHEA gained less weight, had 23% lower eWAT mass and 31% higher serum FFA levels than controls. Cultured explants of eWAT from DHEA-treated rats released 81% more glycerol than those from control rats. DHEA administration upregulated ATGL mRNA (1.62-fold, PHSL mRNA levels (1.36-fold, PHSL (2.49-fold, PHSL, and FAT mRNA levels were positively correlated with PPARγ2 expression. This study demonstrates that DHEA promotes lipid mobilization in adipose tissue by increasing the expression and activity of ATGL and HSL. The effects of DHEA appear to be mediated, at least in part, via PPARγ2 activation, which in turn upregulates ATGL and HSL gene expression.

  1. Production of biodiesel by transesterification of corn and soybean oils with ethanol or butanol using resin-bound truncated Candida antarctica lipase B

    Science.gov (United States)

    Enzymatic catalysts, such as lipases, have advantages over chemical catalysts for transesterification of triglycerides to produce biodiesel. A gene encoding a synthetic truncated Candida antarctica lipase B (CALB) was generated via automated PCR and expressed in Saccharomyces cerevisiae. Western b...

  2. Lipase test

    Science.gov (United States)

    ... the bowel (bowel obstruction) Celiac disease Duodenal ulcer Cancer of the pancreas Infection or swelling of the pancreas This test may also be done for familial lipoprotein lipase deficiency . Risks ... Update Date 2/4/2015 Updated ...

  3. Null Mutation in Hormone-Sensitive Lipase Gene and Risk of Type 2 Diabetes

    Science.gov (United States)

    Albert, Jessica S.; Yerges-Armstrong, Laura M.; Horenstein, Richard B.; Pollin, Toni I.; Sreenivasan, Urmila T.; Chai, Sumbul; Blaner, William S.; Snitker, Soren; O'Connell, Jeffrey R.; Gong, Da-Wei; Breyer, Richard J.; Ryan, Alice S.; McLenithan, John C.; Shuldiner, Alan R.

    2014-01-01

    BACKGROUND Lipolysis regulates energy homeostasis through the hydrolysis of intracellular triglycerides and the release of fatty acids for use as energy substrates or lipid mediators in cellular processes. Genes encoding proteins that regulate energy homeostasis through lipolysis are thus likely to play an important role in determining susceptibility to metabolic disorders. METHODS We sequenced 12 lipolytic-pathway genes in Old Order Amish participants whose fasting serum triglyceride levels were at the extremes of the distribution and identified a novel 19-bp frameshift deletion in exon 9 of LIPE, encoding hormone-sensitive lipase (HSL), a key enzyme for lipolysis. We genotyped the deletion in DNA from 2738 Amish participants and performed association analyses to determine the effects of the deletion on metabolic traits. We also obtained biopsy specimens of abdominal subcutaneous adipose tissue from 2 study participants who were homozygous for the deletion (DD genotype), 10 who were heterozygous (ID genotype), and 7 who were noncarriers (II genotype) for assessment of adipose histologic characteristics, lipolysis, enzyme activity, cytokine release, and messenger RNA (mRNA) and protein levels. RESULTS Carriers of the mutation had dyslipidemia, hepatic steatosis, systemic insulin resistance, and diabetes. In adipose tissue from study participants with the DD genotype, the mutation resulted in the absence of HSL protein, small adipocytes, impaired lipolysis, insulin resistance, and inflammation. Transcription factors responsive to peroxisome-proliferator–activated receptor γ (PPAR-γ) and downstream target genes were down-regulated in adipose tissue from participants with the DD genotype, altering the regulation of pathways influencing adipogenesis, insulin sensitivity, and lipid metabolism. CONCLUSIONS These findings indicate the physiological significance of HSL in adipocyte function and the regulation of systemic lipid and glucose homeostasis and underscore the

  4. Diagnostic value of post-heparin lipase testing in detecting common genetic variants in the LPL and LIPC genes

    OpenAIRE

    van Hoek, Mandy; Dallinga-Thie, Geesje M.; Ewout W Steyerberg; Sijbrands, Eric J. G.

    2009-01-01

    Post-heparin lipoprotein lipase and hepatic lipase activities are used to identify primary disorders of triglyceride and HDL-cholesterol metabolism. Their ability to identify common variants in the lipoprotein lipase (LPL) and hepatic lipase (LIPC) genes is unclear. To investigate the ability of lipase testing to detect common lipase gene variants, we included 183 patients who had undergone post-heparin lipase testing and genotyped the LPL D9N, N291S, PvuII, HindIII, and S447X and the LIPC-51...

  5. Testosterone affects hormone-sensitive lipase (HSL) activity and lipid metabolism in the left ventricle

    DEFF Research Database (Denmark)

    Langfort, Jozef; Jagsz, Slawomir; Dobrzyn, Pawel;

    2010-01-01

    Fatty acids, which are the major cardiac fuel, are derived from lipid droplets stored in cardiomyocytes, among other sources. The heart expresses hormone-sensitive lipase (HSL), which regulates triglycerides (TG) breakdown, and the enzyme is under hormonal control. Evidence obtained from adipose...... tissue suggests that testosterone regulates HSL activity. To test whether this is also true in the heart, we measured HSL activity in the left ventricle of sedentary male rats that had been treated with testosterone supplementation or orchidectomy with or without testosterone substitution. Left ventricle...... HSL activity against TG was significantly elevated in intact rats supplemented with testosterone. HSL activity against both TG and diacylglyceride was reduced by orchidectomy, whereas testosterone replacement fully reversed this effect. Moreover, testosterone increased left ventricle free fatty acid...

  6. Effect of medium chain triglycerides on brown adipose tissue in C57BL/6J mice%中链甘油三酯对C57BL/6J小鼠棕色脂肪组织的影响

    Institute of Scientific and Technical Information of China (English)

    张永; 刘英华; 张新胜; 于晓明; 徐庆; 王觐; 宫雪; 杨雪艳; 薛长勇

    2011-01-01

    Objective To study the effect of medium chain triglycerides(MCT) on brown adipose tissue(BAT) in C57BL/6J mice. Methods Thirty male C57BL/6J mice at the age 4-5 weeks, enrolled in this study, were randomly divided into MCT group, LCT group and control group( 10 in each group). Animals in the first two groups were fed with high fat diet containing MCT or LCT, and those in control group were fed with standard chow for 15 weeks. Body weight, subscapular brown fat mass, diet consumption, and uncoupled protein-1(UCP1) expression in BAT of different groups were observed. Results After 15 weeks, the body weight and body fat mass were significantly lower in MCT group than in LCT group(P0.05). The brown fat mass and UCP1 expression were significantly higher in MCT group than in LCT group(P<0.05). Conclusion MCT can inhibit the increase of body mass and accumulation of body fat due to high fat diet by increasing brown fat mass, UCP1 expression and heat production in brown fat tissue.%目的 观察中链甘油三酯(MCT)对C57BL/6J小鼠棕色脂肪组织的影响.方法 选择4-5周龄C57BL/6J雄性小鼠30只,随机分为中链甘油三酯高脂组(MCT),大豆油高脂组(LCT)及普通饲料对照组,每组10只,喂饲15周.观察研究前后各组间小鼠体质量、饲料消耗量及食物功效比、棕色脂肪组织重量差异以及解偶联蛋白-1(UCP1)表达水平的变化.结果 研究结束时,MCT高脂组小鼠的体质量、体脂肪量显著低于LCT组(P<0.05),饲料消耗量MCT组和LCT组之间无统计学差异(P>0.05),MCT组棕色脂肪组织重量及UCP1蛋白表达量显著高于LCT组.结论 MCT可促进棕色脂肪组织增殖,提高棕色脂肪组织UCP1的表达,增强棕色脂肪组织的产热功能,从而抑制高脂饲料诱发的C57BL/6J小鼠体质量增加和体脂肪积累.

  7. Low Nonfasting Triglycerides and Reduced All-Cause Mortality

    DEFF Research Database (Denmark)

    Thomsen, Mette; Varbo, Anette; Tybjærg-Hansen, Anne;

    2014-01-01

    BACKGROUND: Increased nonfasting plasma triglycerides marking increased amounts of cholesterol in remnant lipoproteins are important risk factors for cardiovascular disease, but whether lifelong reduced concentrations of triglycerides on a genetic basis ultimately lead to reduced all......-cause mortality is unknown. We tested this hypothesis. METHODS: Using individuals from the Copenhagen City Heart Study in a mendelian randomization design, we first tested whether low concentrations of nonfasting triglycerides were associated with reduced all-cause mortality in observational analyses (n = 13 957......); second, whether genetic variants in the triglyceride-degrading enzyme lipoprotein lipase, resulting in reduced nonfasting triglycerides and remnant cholesterol, were associated with reduced all-cause mortality (n = 10 208). RESULTS: During a median 24 and 17 years of 100% complete follow-up, 9991...

  8. GPIHBP1 and Plasma Triglyceride Metabolism.

    Science.gov (United States)

    Fong, Loren G; Young, Stephen G; Beigneux, Anne P; Bensadoun, André; Oberer, Monika; Jiang, Haibo; Ploug, Michael

    2016-07-01

    GPIHBP1, a GPI-anchored protein in capillary endothelial cells, is crucial for the lipolytic processing of triglyceride-rich lipoproteins (TRLs). GPIHBP1 shuttles lipoprotein lipase (LPL) to its site of action in the capillary lumen and is essential for the margination of TRLs along capillaries - such that lipolytic processing can proceed. GPIHBP1 also reduces the unfolding of the LPL catalytic domain, thereby stabilizing LPL catalytic activity. Many different GPIHBP1 mutations have been identified in patients with severe hypertriglyceridemia (chylomicronemia), the majority of which interfere with folding of the protein and abolish its capacity to bind and transport LPL. The discovery of GPIHBP1 has substantially revised our understanding of intravascular triglyceride metabolism but has also raised many new questions for future research. PMID:27185325

  9. Triglycerides and cardiovascular disease

    DEFF Research Database (Denmark)

    Nordestgaard, Børge G; Varbo, Anette

    2014-01-01

    After the introduction of statins, clinical emphasis first focussed on LDL cholesterol-lowering, then on the potential for raising HDL cholesterol, with less focus on lowering triglycerides. However, the understanding from genetic studies and negative results from randomised trials that low HDL...... cholesterol might not cause cardiovascular disease as originally thought has now generated renewed interest in raised concentrations of triglycerides. This renewed interest has also been driven by epidemiological and genetic evidence supporting raised triglycerides, remnant cholesterol, or triglyceride......-rich lipoproteins as an additional cause of cardiovascular disease and all-cause mortality. Triglycerides can be measured in the non-fasting or fasting states, with concentrations of 2-10 mmol/L conferring increased risk of cardiovascular disease, and concentrations greater than 10 mmol/L conferring increased risk...

  10. Acid Lipase Disease

    Science.gov (United States)

    ... Enhancing Diversity Find People About NINDS NINDS Acid Lipase Disease Information Page Synonym(s): Cholesterol Ester Storage Disease, ... Related NINDS Publications and Information What is Acid Lipase Disease ? Acid lipase disease or deficiency occurs when ...

  11. Mechanisms of lipase maturation

    OpenAIRE

    Doolittle, Mark H.; Péterfy, Miklós

    2010-01-01

    Lipases are acyl hydrolases that represent a diverse group of enzymes present in organisms ranging from prokaryotes to humans. This article focuses on an evolutionarily related family of extracellular lipases that include lipoprotein lipase, hepatic lipase and endothelial lipase. As newly synthesized proteins, these lipases undergo a series of co- and post-translational maturation steps occurring in the endoplasmic reticulum, including glycosylation and glycan processing, and protein folding ...

  12. Isolation and characterization of some moderately halophilic bacteria with lipase activity.

    Science.gov (United States)

    Ghasemi, Y; Rasoul-Amini, S; Kazemi, A; Zarrinic, G; Morowvat, M H; Kargar, M

    2011-01-01

    Lipases are an important class of enzymes which catalyze the hydrolysis of long chain triglycerides and constitute the most prominent group ofbiocatalysts for biotechnological applications. There are a number of lipases, produced by some halophilic microorganisms. In this study, some lipase producing bacteria from Maharlu salt lake located in south of Iran were isolated. All isolates were screened for true lipase activity on plates containing olive oil. The lipase activity was measured using titrimetric methods. Among thirty three isolates, thirteen strains demonstrating orange zone around colonies under UV light, were selected for identification using the molecular methods and some morphological characteristics. The bacterium Bacillus vallismortis BCCS 007 with 3.41 +/- 0.14 U/mL lipase activity was selected as the highest lipase producing isolate. This is the first report of isolation and molecular identification of lipase producing bacteria from Maharlu lake. PMID:22073547

  13. Augmented expression and secretion of adipose-derived pigment epithelium-derived factor does not alter local angiogenesis or contribute to the development of systemic metabolic derangements.

    Science.gov (United States)

    Lakeland, Thomas V; Borg, Melissa L; Matzaris, Maria; Abdelkader, Amany; Evans, Roger G; Watt, Matthew J

    2014-06-15

    Impaired coupling of adipose tissue expansion and vascularization is proposed to lead to adipocyte hypoxia and inflammation, which in turn contributes to systemic metabolic derangements. Pigment epithelium-derived factor (PEDF) is a powerful antiangiogenic factor that is secreted by adipocytes, elevated in obesity, and implicated in the development of insulin resistance. We explored the angiogenic and metabolic role of adipose-derived PEDF through in vivo studies of mice with overexpression of PEDF in adipocytes (PEDF-aP2). PEDF expression in white adipocytes and PEDF secretion from adipose tissue was increased in transgenic mice, but circulating levels of PEDF were not increased. Overexpression of PEDF did not alter vascularization, the partial pressure of O2, cellular hypoxia, or gene expression of inflammatory markers in adipose tissue. Energy expenditure and metabolic substrate utilization, body mass, and adiposity were not altered in PEDF-aP2 mice. Whole body glycemic control was normal as assessed by glucose and insulin tolerance tests, and adipocyte-specific glucose uptake was unaffected by PEDF overexpression. Adipocyte lipolysis was increased in PEDF-aP2 mice and associated with increased adipose triglyceride lipase and decreased perilipin 1 expression. Experiments conducted in mice rendered obese by high-fat feeding showed no differences between PEDF-aP2 and wild-type mice for body mass, adiposity, whole body energy expenditure, glucose tolerance, or adipose tissue oxygenation. Together, these data indicate that adipocyte-generated PEDF enhances lipolysis but question the role of PEDF as a major antiangiogenic or proinflammatory mediator in adipose tissue in vivo.

  14. Combined Insulin Deficiency and Endotoxin Exposure Stimulate Lipid Mobilization and Alter Adipose Tissue Signaling in an Experimental Model of Ketoacidosis in Subjects With Type 1 Diabetes: A Randomized Controlled Crossover Trial.

    Science.gov (United States)

    Svart, Mads; Kampmann, Ulla; Voss, Thomas; Pedersen, Steen B; Johannsen, Mogens; Rittig, Nikolaj; Poulsen, Per L; Nielsen, Thomas S; Jessen, Niels; Møller, Niels

    2016-05-01

    Most often, diabetic ketoacidosis (DKA) in adults results from insufficient insulin administration and acute infection. DKA is assumed to release proinflammatory cytokines and stress hormones that stimulate lipolysis and ketogenesis. We tested whether this perception of DKA can be reproduced in an experimental human model by using combined insulin deficiency and acute inflammation and tested which intracellular mediators of lipolysis are affected in adipose tissue. Nine subjects with type 1 diabetes were studied twice: 1) insulin-controlled euglycemia and 2) insulin deprivation and endotoxin administration (KET). During KET, serum tumor necrosis factor-α, cortisol, glucagon, and growth hormone levels increased, and free fatty acids and 3-hydroxybutyrate concentrations and the rate of lipolysis rose markedly. Serum bicarbonate and pH decreased. Adipose tissue mRNA contents of comparative gene identification-58 (CGI-58) increased and G0/G1 switch 2 gene (G0S2) mRNA decreased robustly. Neither protein levels of adipose triglyceride lipase (ATGL) nor phosphorylations of hormone-sensitive lipase were altered. The clinical picture of incipient DKA in adults can be reproduced by combined insulin deficiency and endotoxin-induced acute inflammation. The precipitating steps involve the release of proinflammatory cytokines and stress hormones, increased lipolysis, and decreased G0S2 and increased CGI-58 mRNA contents in adipose tissue, compatible with latent ATGL stimulation. PMID:26884439

  15. Cloning and functional characterization of the ovine Hormone Sensitive Lipase (HSL) full-length cDNAs: an integrated approach.

    Science.gov (United States)

    Lampidonis, Antonis D; Argyrokastritis, Alexandros; Stravopodis, Dimitrios J; Voutsinas, Gerassimos E; Ntouroupi, Triantafyllia G; Margaritis, Lukas H; Bizelis, Iosif; Rogdakis, Emmanuel

    2008-06-15

    Hormone Sensitive Lipase (HSL) is a highly regulated enzyme that mediates lipolysis in adipocytes. HSL enzymatic activity is increased by adrenergic agonists, such as catecholamines and glucagons, which induce cyclic AMP (cAMP) intracellular production, subsequently followed by the activation of Protein Kinase A (PKA) and its downstream signalling cascade reactions. Since HSL constitutes the key enzyme in the regulation of lipid stores and the only enzyme being subjected to hormonal regulation [in terms of the recently identified Adipose Triglyceride Lipase (ATGL)], the ovine Hormone Sensitive Lipase (ovHSL) full-length cDNA clones were isolated, using a Polymerase Chain Reaction-based (PCR) strategy. The two isolated isoforms ovHSL-A and ovHSL-B contain two highly homologous Open Reading Frame (ORF) regions of 2.089 Kb and 2.086 Kb, respectively, the latter having been missed the 688th triplet coding for glutamine (DeltaQ(688)). The putative 695 and 694 amino acid respective sequences bear strong homologies with other HSL protein family members. Southern blotting analysis revealed that HSL is represented as a single copy gene in the ovine genome, while Reverse Transcription-PCR (RT-PCR) approaches unambiguously dictated its variable transcriptional expression profile in the different tissues examined. Interestingly, as undoubtedly corroborated by both RT-PCR and Western blotting analysis, ovHSL gene expression is notably enhanced in the adipose tissue during the fasting period, when lipolysis is highly increased in ruminant species. Based on the crystal structure of an Archaeoglobus fulgidus enzyme, a three-dimensional (3D) molecular model of the ovHSL putative catalytic domain was constructed, thus providing an inchoative insight into understanding the enzymatic activity and functional regulation mechanisms of the ruminant HSL gene product(s).

  16. Optimization of conjugated linoleic acid triglycerides via enzymatic esterification in no-solvent system

    Institute of Scientific and Technical Information of China (English)

    YI Dan; SUN Xiuqin; LI Guangyou; LIU Fayi; LIN Xuezheng; SHEN Jihong

    2009-01-01

    We compared four esterifiable enzymes. The lipase Novozym 435 possessed the highest activity for the conjugated linoleic acid esterification during the synthesis of triglycerides. The triglycerides were synthesized by esterification of glycerol and conjugated linoleic acid (CLA) in a no-solvent system using lipase catalysis. We investigated the effects of temperature, enzyme concentration, water content, and time on esterification. Enzyme and water concentrations of up to 1% of the total reaction volume and a system temperature of 60°C proved optimal for esterification. Similarly, when the esterification was carried out for 24 h, the reaction ratio improved to 94.11%. The esterification rate of the rotating screen basket remained high (87.28%) when the enzyme was re-used for the 5th time. We evaluated the substrate selectivity of lipase (NOVO 435) and determined that this lipase prefers the 10,12-octadacadienoic acid to the 9,11-octadecadienoic acid.

  17. Modest hypoxia significantly reduces triglyceride content and lipid droplet size in 3T3-L1 adipocytes

    International Nuclear Information System (INIS)

    Highlights: •Long-term hypoxia decreased the size of LDs and lipid storage in 3T3-L1 adipocytes. •Long-term hypoxia increased basal lipolysis in 3T3-L1 adipocytes. •Hypoxia decreased lipid-associated proteins in 3T3-L1 adipocytes. •Hypoxia decreased basal glucose uptake and lipogenic proteins in 3T3-L1 adipocytes. •Hypoxia-mediated lipogenesis may be an attractive therapeutic target against obesity. -- Abstract: Background: A previous study has demonstrated that endurance training under hypoxia results in a greater reduction in body fat mass compared to exercise under normoxia. However, the cellular and molecular mechanisms that underlie this hypoxia-mediated reduction in fat mass remain uncertain. Here, we examine the effects of modest hypoxia on adipocyte function. Methods: Differentiated 3T3-L1 adipocytes were incubated at 5% O2 for 1 week (long-term hypoxia, HL) or one day (short-term hypoxia, HS) and compared with a normoxia control (NC). Results: HL, but not HS, resulted in a significant reduction in lipid droplet size and triglyceride content (by 50%) compared to NC (p < 0.01). As estimated by glycerol release, isoproterenol-induced lipolysis was significantly lowered by hypoxia, whereas the release of free fatty acids under the basal condition was prominently enhanced with HL compared to NC or HS (p < 0.01). Lipolysis-associated proteins, such as perilipin 1 and hormone-sensitive lipase, were unchanged, whereas adipose triglyceride lipase and its activator protein CGI-58 were decreased with HL in comparison to NC. Interestingly, such lipogenic proteins as fatty acid synthase, lipin-1, and peroxisome proliferator-activated receptor gamma were decreased. Furthermore, the uptake of glucose, the major precursor of 3-glycerol phosphate for triglyceride synthesis, was significantly reduced in HL compared to NC or HS (p < 0.01). Conclusion: We conclude that hypoxia has a direct impact on reducing the triglyceride content and lipid droplet size via

  18. Modest hypoxia significantly reduces triglyceride content and lipid droplet size in 3T3-L1 adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Takeshi, E-mail: thashimo@fc.ritsumei.ac.jp [Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577 (Japan); Yokokawa, Takumi; Endo, Yuriko [Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577 (Japan); Iwanaka, Nobumasa [Ritsumeikan Global Innovation Research Organization, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577 (Japan); Higashida, Kazuhiko [Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577 (Japan); Faculty of Sport Science, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192 (Japan); Taguchi, Sadayoshi [Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577 (Japan)

    2013-10-11

    Highlights: •Long-term hypoxia decreased the size of LDs and lipid storage in 3T3-L1 adipocytes. •Long-term hypoxia increased basal lipolysis in 3T3-L1 adipocytes. •Hypoxia decreased lipid-associated proteins in 3T3-L1 adipocytes. •Hypoxia decreased basal glucose uptake and lipogenic proteins in 3T3-L1 adipocytes. •Hypoxia-mediated lipogenesis may be an attractive therapeutic target against obesity. -- Abstract: Background: A previous study has demonstrated that endurance training under hypoxia results in a greater reduction in body fat mass compared to exercise under normoxia. However, the cellular and molecular mechanisms that underlie this hypoxia-mediated reduction in fat mass remain uncertain. Here, we examine the effects of modest hypoxia on adipocyte function. Methods: Differentiated 3T3-L1 adipocytes were incubated at 5% O{sub 2} for 1 week (long-term hypoxia, HL) or one day (short-term hypoxia, HS) and compared with a normoxia control (NC). Results: HL, but not HS, resulted in a significant reduction in lipid droplet size and triglyceride content (by 50%) compared to NC (p < 0.01). As estimated by glycerol release, isoproterenol-induced lipolysis was significantly lowered by hypoxia, whereas the release of free fatty acids under the basal condition was prominently enhanced with HL compared to NC or HS (p < 0.01). Lipolysis-associated proteins, such as perilipin 1 and hormone-sensitive lipase, were unchanged, whereas adipose triglyceride lipase and its activator protein CGI-58 were decreased with HL in comparison to NC. Interestingly, such lipogenic proteins as fatty acid synthase, lipin-1, and peroxisome proliferator-activated receptor gamma were decreased. Furthermore, the uptake of glucose, the major precursor of 3-glycerol phosphate for triglyceride synthesis, was significantly reduced in HL compared to NC or HS (p < 0.01). Conclusion: We conclude that hypoxia has a direct impact on reducing the triglyceride content and lipid droplet size via

  19. Endothelial lipase is a major determinant of HDL level

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, Tatsuro; Choi, Sungshin; Kundu, Ramendra K.; Hirata, Ken-Ichi; Rubin, Edward M.; Cooper, Allen D.; Quertermous, Thomas

    2003-01-30

    For the past three decades, epidemiologic studies have consistently demonstrated an inverse relationship between plasma HDL cholesterol (HDL-C) concentrations and coronary heart disease (CHD). Population-based studies have provided compelling evidence that low HDL-C levels are a risk factor for CHD, and several clinical interventions that increased plasma levels of HDL-C were associated with a reduction in CHD risk. These findings have stimulated extensive investigation into the determinants of plasma HDL-C levels. Turnover studies using radiolabeled apolipoprotein A-I, the major protein component of HDL, suggest that plasma HDL-C concentrations are highly correlated with the rate of clearance of apolipoprotein AI. However, the metabolic mechanisms by which HDL are catabolized have not been fully defined. Previous studies in humans with genetic deficiency of cholesteryl ester transfer protein, and in mice lacking the scavenger receptor BI (SR-BI), have demonstrated that these proteins participate in the removal of cholesterol from HDL, while observations in individuals with mutations in hepatic lipase indicate that this enzyme hydrolyzes HDL triglycerides. In this issue of the JCI, reports from laboratories of Tom Quertermous and Dan Rader now indicate that endothelial lipase (LIPG), a newly identified member of the lipase family, catalyzes the hydrolysis of HDL phospholipids and facilitates the clearance of HDL from the circulation. Endothelial lipase was initially cloned by both of these laboratories using entirely different strategies. Quertermous and his colleagues identified endothelial lipase as a transcript that was upregulated in cultured human umbilical vein endothelial cells undergoing tube formation, whereas the Rader group cloned endothelial lipase as a transcript that was upregulated in the human macrophage-like cell line THP-1 exposed to oxidized LDL. Database searches revealed that endothelial lipase shows strong sequence similarity to lipoprotein

  20. Biosensor Applications of MAPLE Deposited Lipase

    Directory of Open Access Journals (Sweden)

    Valeria Califano

    2014-10-01

    Full Text Available Matrix Assisted Pulsed Laser Evaporation (MAPLE is a thin film deposition technique derived from Pulsed Laser Deposition (PLD for deposition of delicate (polymers, complex biological molecules, etc. materials in undamaged form. The main difference of MAPLE technique with respect to PLD is the target: it is a frozen solution or suspension of the (guest molecules to be deposited in a volatile substance (matrix. Since laser beam energy is mainly absorbed by the matrix, damages to the delicate guest molecules are avoided, or at least reduced. Lipase, an enzyme catalyzing reactions borne by triglycerides, has been used in biosensors for detection of β-hydroxyacid esters and triglycerides in blood serum. Enzymes immobilization on a substrate is therefore required. In this paper we show that it is possible, using MAPLE technique, to deposit lipase on a substrate, as shown by AFM observation, preserving its conformational structure, as shown by FTIR analysis.

  1. Colipase enhances hydrolysis of dietary triglycerides in the absence of bile salts.

    Science.gov (United States)

    Bläckberg, L; Hernell, O; Bengtsson, G; Olivecrona, T

    1979-11-01

    This study explores how dietary lipids are digested when intraduodenal bile salts are low or absent. Long-chain triglycerides emulsified with phosphatidylcholine were found to be hydrolyzed very slowly by pancreatic lipase alone, as if the surface layer of phospholipids enveloping the triglycerides impeded the action of the enzyme. Colipase enhanced triglyceride hydrolysis severalfold, both when added before or after the lipase. Hydrolysis became even more rapid when the emulsion was first incubated with pancreatic phospholipase. Hydrolysis of long-chain triglycerides was also severely impeded when other proteins were added to the system, probably because they adsorbed to the oil-water interface of the emulsion droplets. It was previously known that bile salts can relieve such inhibition, presumably by desorbing the adsorbed proteins. Colipase was found to enhance hydrolysis severalfold in a dose-dependent manner even in the absence of bile salts, i.e., it could partially or completely relieve the inhibition depending upon the amount and the type of inhibitory protein added to the system. Prior exposure of a protein-coated triglyceride emulsion to another lipase also enhanced the rate at which pancreatic lipase could then hydrolyze the lipids. Most dietary triglycerides are probably presented for intestinal digestion in emulsions covered by proteins and/or phospholipids. These emulsions would be hydrolyzed slowly by pancreatic lipase alone. However, through the action of the lipase in stomach contents and of pancreatic phospholipase and through the lipolysis-promoting effects of collipase, these triglycerices can be rather efficiently hydrolyzed, even in the absence of bile salts.

  2. Overexpression of G0/G1 Switch Gene 2 in Adipose Tissue of Transgenic Quail Inhibits Lipolysis Associated with Egg Laying

    Directory of Open Access Journals (Sweden)

    Paula Renee Chen

    2016-03-01

    Full Text Available In avians, yolk synthesis is regulated by incorporation of portomicrons from the diet, transport of lipoproteins from the liver, and release of lipids from adipose tissue; however, the extent to which lipolysis in adipose tissue contributes to yolk synthesis and egg production has yet to be elucidated. G0/G1 switch gene 2 (G0S2 is known to bind and inhibit adipose triglyceride lipase (ATGL, the rate-limiting enzyme in lipolysis. The objective of this study was to determine whether overexpression of the G0S2 gene in adipose tissue could successfully inhibit endogenous ATGL activity associated with egg laying. Two independent lines of transgenic quail overexpressing G0S2 had delayed onset of egg production and reduced number of eggs over a six-week period compared to non-transgenic quail. Although no differences in measured parameters were observed at the pre-laying stage (5 weeks of age, G0S2 transgenic quail had significantly larger interclavicular fat pad weights and adipocyte sizes and lower NEFA concentrations in the serum at early (1 week after laying first egg and active laying (5 weeks after laying first egg stages. Overexpression of G0S2 inhibited lipolysis during early and active laying, which drastically shifted the balance towards a net accumulation of triacylglycerols and increased adipose tissue mass. Thereby, egg production was negatively affected as less triacylglycerols were catabolized to produce lipids for the yolk.

  3. Endothelial and lipoprotein lipases in human and mouse placenta

    DEFF Research Database (Denmark)

    Lindegaard, Marie L S; Olivecrona, Gunilla; Christoffersen, Christina;

    2005-01-01

    Placenta expresses various lipase activities. However, a detailed characterization of the involved genes and proteins is lacking. In this study, we compared the expression of endothelial lipase (EL) and LPL in human term placenta. When placental protein extracts were separated by heparin......-Sepharose affinity chromatography, the EL protein eluted as a single peak without detectable phospholipid or triglyceride (TG) lipase activity. The major portion of LPL protein eluted slightly after EL. This peak also had no lipase activity and most likely contained monomeric LPL. Fractions eluting at a higher Na......Cl concentration contained small amounts of LPL protein (most likely dimeric LPL) and had substantial TG lipase activity. In situ hybridization studies showed EL mRNA expression in syncytiotrophoblasts and endothelial cells and LPL mRNA in syncytiotrophoblasts. In contrast, immunohistochemistry showed EL and LPL...

  4. Expression of lipases and lipid receptors in sperm storage tubules and possible role of fatty acids in sperm survival in the hen oviduct.

    Science.gov (United States)

    Huang, A; Isobe, N; Obitsu, T; Yoshimura, Y

    2016-04-15

    The aim of this study was to determine the role of fatty acids for sperm survival in the sperm storage tubules (SSTs) of the hen oviduct. The mucosa tissues of uterovaginal junction (UVJ) of White Leghorn laying hens with or without artificial insemination using semen from Barred Plymouth Rock roosters were collected. The lipid density in the epithelium of UVJ and SST was analyzed by Sudan black B staining. The expressions of genes encoding lipid receptors and lipases were assayed by polymerase chain reaction in UVJ mucosa and SST cells isolated by laser microdissection. Fatty acid composition was analyzed by gas chromatography, and sperm were cultured with or without the identified predominant fatty acids for 24 hours to examine their effect on sperm viability. The lipid droplets were localized in the epithelium of UVJ mucosa and SSTs. The expression of genes encoding very low-density lipoprotein receptor(VLDLR), low-density lipoprotein receptor (LDLR), and fatty acid translocase (FAT/CD36) were found in SST cells. Expression of genes encoding endothelial lipase (EL), lipase H (LIPH), adipose triglyceride lipase (ATGL), and lipoprotein lipase (LPL) were found in UVJ. In contrast, only ATGL was found in SST cells, and its expression was significantly upregulated after artificial insemination. In UVJ mucosal tissues, five fatty acids, namely myristic acid (C14), palmitic acid (C16), stearic acid (C18), oleic acid (C18:1n9), and linoleic acid (C18:2n6), were identified as predominant fatty acids. The viability of sperm cultured with 1 mM oleic acid or linoleic acid was significantly higher than the sperm in the control culture without fatty acids. These results suggest that lipids in the SST cells may be degraded by ATGL, and fatty acids including oleic acid and linoleic acid may be released into the SST lumen to support sperm survival. PMID:26777559

  5. Sympathetic nervous system control of triglyceride metabolism: Novel concepts derived from recent studies

    NARCIS (Netherlands)

    Geerling, J.J.; Boon, M.R.; Kooijman, S.; Parlevliet, E.T.; Havekes, L.M.; Romijn, J.A.; Meurs, I.M.; Rensen, P.C.N.

    2014-01-01

    Abstract Important players in triglyceride (TG) metabolism include the liver (production), white adipose tissue (WAT) (storage), heart and skeletal muscle (combustion to generate ATP), and brown adipose tissue (BAT) (combustion toward heat), the collective action of which determine plasma TG levels.

  6. Fasting for 21days leads to changes in adipose tissue and liver physiology in juvenile checkered garter snakes (Thamnophis marcianus).

    Science.gov (United States)

    Davis, Mary; Jessee, Renee; Close, Matthew; Fu, Xiangping; Settlage, Robert; Wang, Guoqing; Cline, Mark A; Gilbert, Elizabeth R

    2015-12-01

    Snakes often undergo periods of prolonged fasting and, under certain conditions, can survive years without food. Despite this unique phenomenon, there are relatively few reports of the physiological adaptations to fasting in snakes. At post-prandial day 1 (fed) or 21 (fasting), brain, liver, and adipose tissues were collected from juvenile checkered garter snakes (Thamnophis marcianus). There was greater glycerol-3-phosphate dehydrogenase (G3PDH)-specific activity in the liver of fasted than fed snakes (P=0.01). The mRNA abundance of various fat metabolism-associated factors was measured in brain, liver, and adipose tissue. Lipoprotein lipase (LPL) mRNA was greater in fasted than fed snakes in the brain (P=0.04). Adipose triglyceride lipase (ATGL; P=0.006) mRNA was greater in the liver of fasted than fed snakes. In adipose tissue, expression of peroxisome proliferator-activated receptor (PPAR)γ (P=0.01), and fatty acid binding protein 4 (P=0.03) was greater in fed than fasted snakes. Analysis of adipocyte morphology revealed that cross-sectional area (P=0.095) and diameter (P=0.27) were not significantly different between fed and fasted snakes. Results suggest that mean adipocyte area can be preserved during fasting by dampening lipid biosynthesis while not changing rates of lipid hydrolysis. In the liver, however, extensive lipid remodeling may provide energy and lipoproteins to maintain lipid structural integrity during energy restriction. Because the duration of fasting was not sufficient to change adipocyte size, results suggest that the liver is important as a short-term provider of energy in the snake.

  7. Gut triglyceride production.

    Science.gov (United States)

    Pan, Xiaoyue; Hussain, M Mahmood

    2012-05-01

    Our knowledge of how the body absorbs triacylglycerols (TAG) from the diet and how this process is regulated has increased at a rapid rate in recent years. Dietary TAG are hydrolyzed in the intestinal lumen to free fatty acids (FFA) and monoacylglycerols (MAG), which are taken up by enterocytes from their apical side, transported to the endoplasmic reticulum (ER) and resynthesized into TAG. TAG are assembled into chylomicrons (CM) in the ER, transported to the Golgi via pre-chylomicron transport vesicles and secreted towards the basolateral side. In this review, we mainly focus on the roles of key proteins involved in uptake and intracellular transport of fatty acids, their conversion to TAG and packaging into CM. We will also discuss intracellular transport and secretion of CM. Moreover, we will bring to light few factors that regulate gut triglyceride production. Furthermore, we briefly summarize pathways involved in cholesterol absorption. This article is part of a Special Issue entitled Triglyceride Metabolism and Disease.

  8. Familial lipoprotein lipase deficiency

    Science.gov (United States)

    ... medlineplus.gov/ency/article/000408.htm Familial lipoprotein lipase deficiency To use the sharing features on this page, please enable JavaScript. Familial lipoprotein lipase deficiency is a group of rare genetic disorders ...

  9. Optimasi Produksi Enzim Lipase dari Bakteri Sumber Air Panas Tamalantik, Mamasa Sulawesi Barat

    OpenAIRE

    Tunggala, Stephanie; Natsir, Hasnah; Hariani, Nunuk

    2014-01-01

    Lipase (EC 3.1.1.3) is one of class hydrolase enzymes that can hydrolyze triglycerides into fatty acids and glycerol. This research determine the optimum conditions of lipase production from Bacillus isolates sp.TM_2a.2 which isolated from hot spring Tamalantik, Mamasa, West Celebes with Various of substrat concentration (olive oil) is 0.2%, 0.4%, 0, 6%, 0.8% and 1%. The activity of lipase production was tested by titrimetric method. The results show that the lipase produced optimum at subst...

  10. Study of enzymatic reactors with microencapsulated lipase. Doctoral thesis. Estudo de reactores enzimaticos com lipase microencapsulada

    Energy Technology Data Exchange (ETDEWEB)

    de Franca Teixeira dos Prazeres, D.M.

    1992-10-01

    The work reports the development of a membrane reactor for the hydrolysis of triglycerides catalyzed by lipase B from Chromobacterium viscosum in AOT/isooctane reversed miceller system. In a preliminary phase the potential of the organic system was evaluated with comparative studies on the activity and stability of lipase B in aqueous media (emulsion) and in the alternative miceller media. A tubular ceramic membrane reactor with recirculation was selected for the olive oil hydrolysis in a reversed miceller system. The influence of the hydration degree, recirculation rate, AOT, olive oil and lipase concentration in the operation of the reactor were investigated in a batch mode. The hydration degree was identified as a critical parameter due to its influence in the separation process and in the kinetics of the reaction.

  11. Lipoprotein lipase deficiency.

    OpenAIRE

    Shankar K; Bava H; Shetty J; Joshi M

    1997-01-01

    A rare case of a 3 month old child with lipoprotein lipase deficiency who presented with bronchopneumonia is reported. After noticing lipaemic serum and lipaemia retinalis, a diagnosis of hyperlipoproteinaemia was considered. Lipoprotein lipase deficiency was confirmed with post heparin lipoprotein lipase enzyme activity estimation.

  12. Pancreatic lipase-related protein 2 digests fats in human milk and formula in concert with gastric lipase and carboxyl ester lipase

    Science.gov (United States)

    Johnson, Karin; Ross, Leah; Miller, Rita; Xiao, Xunjun; Lowe, Mark E.

    2013-01-01

    INTRODUCTION Dietary fats must be digested into fatty acids and monoacylglycerols prior to absorption. In adults, colipase-dependent pancreatic triglyceride lipase (PTL) contributes significantly to fat digestion. In newborn rodents and humans, the pancreas expresses low levels of PTL. In rodents, a homologue of PTL, pancreatic lipase related protein 2 (PLRP2) and carboxyl ester lipase (CEL) compensate for the lack of PTL. In human newborns, the role for PLRP2 in dietary fat digestion is unclear. To clarify the potential of human PLRP2 to influence dietary fat digestion in newborns, we determined PLRP2 activity against human milk and infant formula. METHODS The activity of purified recombinant PLRP2, gastric lipase and CEL against fats in human milk and formula was measured with each lipase alone and in combination with a standard pH-stat assay. RESULTS Colipase added to human milk stimulated fat digestion. PLRP2 and CEL had activity against human milk and formula. Pre-digestion with gastric lipase increased PLRP2 activity against both substrates. Together, CEL and PLRP2 activity was additive with formula and synergistic with human milk. CONCLUSIONS PLRP2 can digest fats in human milk and formula. PLRP2 acts in concert with CEL and gastric lipase to digest fats in human milk in vitro. PMID:23732775

  13. The specificity of Several Kinds Lipases on n-3 Polyunsaturated Fatty Acids

    Directory of Open Access Journals (Sweden)

    Jenny Elisabeth, T Yuliani, P M Tambunan, J M Purba

    2001-04-01

    Full Text Available Several lipases from microbial and plant, i.e Rhizomucor miehei, Pseudomonas sp., Candida antartica, rice bran, and Carica papaya latex (CPL were examined for synthesis of omega-3 (n-3 PUFA-rich glyceride by hydrolysis and acidolysis reaction. Tuna oil was used in hydrolysis reaction, whereas tuna and palm oils were used as source of triglyceride (TAG molecules and n-3 PUFA concentrate from tuna oil as source of EPA and DHA in acidolysis reaction.For hydrolysis reaction, the rice bran and CPL lipases showed the lowest hydrolytic activity of the tuna oil, whereas the R. miehei lipase showed the highest hydrolytic activity but was unable to hydrolyze EPA and DHA. On the contrary, the C. antartica and Pseudomonas sp. lipases acted stronger on hydrolysis of DHA ester bond than EPA.For acidolysis reaction, all the lipases showed ability to incorporate n-3 PUFA into tuna and palm oils. C. antartica lipase had the maximum DHA incorporation into tuna and palm oils, rice bran lipase had relatively similar ability with R. miehei lipase, and the CPL lipase had the lowest ability. This study proved that rice bran and CPL lipases also had transesterification activity and showed the feasibility of the rice bran lipase to be a biocatalyst for n-3 PUFA-rich glyceride production. Increasing the substrate ratio, of n-3 PUFA concentrate and tuna or palm oil, could increase the EPA and DHA incorporation. The R. miehei, rice bran, and CPL lipases unabled to incorporate DHA into DHA-containing glyceride molecule, whereas C. antartica lipase had the capability in high ratio of n-3 PUFA concentrate to oil. Therefore, the lipases were easier to incorporate n-3 PUFA into palm oil than tuna oil, since the TAG molecules of palm oil was not as complex as tuna oil. It could be suggested that the lipases did not only have acyl chain and positional specificity, but also the whole glyceride structure specificity.

  14. Dietary conjugated linoleic acid induces lipolysis in adipose tissue of coconut oil-fed mice but not soy oil-fed mice.

    Science.gov (United States)

    Ippagunta, S; Hadenfeldt, T J; Miner, J L; Hargrave-Barnes, K M

    2011-09-01

    Mice fed diets containing conjugated linoleic acid (CLA) are leaner than mice not fed CLA. This anti-obesity effect is amplified in mice fed coconut oil-containing or fat free diets, compared to soy oil diets. The present objective was to determine if CLA alters lipolysis in mice fed different base oils. Mice were fed diets containing soy oil (SO), coconut oil (CO), or fat free (FF) for 6 weeks, followed by 10 or 12 days of CLA or no CLA supplementation. Body fat, tissue weights, and ex vivo lipolysis were determined. Relative protein abundance and activation of perilipin, hormone sensitive lipase (HSL), adipose triglyceride lipase (ATGL), and adipose differentiation related protein (ADRP) were determined by western blotting. CLA feeding caused mice to have less (P oil source, P oil source interaction on lipolysis as CO + CLA and FF + CLA-fed mice had increased (P < 0.05) rates of lipolysis but SO + CLA-fed mice did not. However, after 12 days of CLA consumption, activated perilipin was increased (P < 0.05) only in SO + CLA-fed mice and total HSL and ATGL were decreased (P < 0.05) in CO + CLA-fed mice. Therefore, the enhanced CLA-induced body fat loss in CO and FF-fed mice appears to involve increased lipolysis but this effect may be decreasing by 12 days of CLA consumption.

  15. Homology of lipoprotein lipase to pancreatic lipase.

    OpenAIRE

    Ben-Avram, C M; Ben-Zeev, O; Lee, T.D. (Taunia D.); Haaga, K; Shively, J. E.; Goers, J; Pedersen, M.E; Reeve, J R; Schotz, M C

    1986-01-01

    Bovine milk lipoprotein lipase was subjected to amino acid sequence analysis. The first 19 amino-terminal residues were Asp-Arg-Ile-Thr-Gly-Gly-Lys-Asp-Phe-Arg-Asp-Ile-Glu-Ser-Lys-Phe-Ala-Leu- Arg. In addition, reversed-phase high-performance liquid chromatography of a tryptic digest of reduced and alkylated lipase resolved a number of peptides, five of which contained cysteine. Sequence analysis of the tryptic peptides revealed in most instances a close homology to porcine pancreatic lipase....

  16. High-fat diet-mediated lipotoxicity and insulin resistance is related to impaired lipase expression in mouse skeletal muscle.

    Science.gov (United States)

    Badin, Pierre-Marie; Vila, Isabelle K; Louche, Katie; Mairal, Aline; Marques, Marie-Adeline; Bourlier, Virginie; Tavernier, Geneviève; Langin, Dominique; Moro, Cedric

    2013-04-01

    Elevated expression/activity of adipose triglyceride lipase (ATGL) and/or reduced activity of hormone-sensitive lipase (HSL) in skeletal muscle are causally linked to insulin resistance in vitro. We investigated here the effect of high-fat feeding on skeletal muscle lipolytic proteins, lipotoxicity, and insulin signaling in vivo. Five-week-old C3H mice were fed normal chow diet (NCD) or 45% kcal high-fat diet (HFD) for 4 weeks. Wild-type and HSL knockout mice fed NCD were also studied. Whole-body and muscle insulin sensitivity, as well as lipolytic protein expression, lipid levels, and insulin signaling in skeletal muscle, were measured. HFD induced whole-body insulin resistance and glucose intolerance and reduced skeletal muscle glucose uptake compared with NCD. HFD increased skeletal muscle total diacylglycerol (DAG) content, protein kinase Cθ and protein kinase Cε membrane translocation, and impaired insulin signaling as reflected by a robust increase of basal Ser1101 insulin receptor substrate 1 phosphorylation (2.8-fold, P < .05) and a decrease of insulin-stimulated v-Akt murine thymoma viral oncogene homolog Ser473 (-37%, P < .05) and AS160 Thr642 (-47%, P <.01) phosphorylation. We next showed that HFD strongly reduced HSL phosphorylation at Ser660. HFD significantly up-regulated the muscle protein content of the ATGL coactivator comparative gene identification 58 and triacylglycerol hydrolase activity, despite a lower ATGL protein content. We further show a defective skeletal muscle insulin signaling and DAG accumulation in HSL knockout compared with wild-type mice. Together, these data suggest a pathophysiological link between altered skeletal muscle lipase expression and DAG-mediated insulin resistance in mice. PMID:23471217

  17. Relationship between common lipoprotein lipase gene sequence variants, hyperinsulinemia, and risk of ischemic heart disease: A population-based study

    DEFF Research Database (Denmark)

    Jeppesen, Jørgen; Hansen, Tine Willum; Torp-Pedersen, Christian;

    2010-01-01

    Hyperinsulinemia and lipoprotein lipase (LPL) are important determinants of fasting and postprandial plasma triglyceride levels. High insulin and high triglyceride levels are associated with an increased risk of ischemic heart disease (IHD). This study aimed to find out whether common LPL gene...... sequence variants could change the relationship between insulin and IHD....

  18. Evaluation of a New Lipase from Staphylococcus sp. for Detergent Additive Capability

    Directory of Open Access Journals (Sweden)

    Mamta Chauhan

    2013-01-01

    Full Text Available Lipases are the enzymes of choice for laundry detergent industries owing to their triglyceride removing ability from the soiled fabric which eventually reduces the usage of phosphate-based chemical cleansers in the detergent formulation. In the present study, a partially purified bacterial lipase from Staphylococcus arlettae JPBW-1 isolated from the rock salt mine has been assessed for its triglyceride removing ability by developing a presoak solution so as to use lipase as an additive in laundry detergent formulations. The effects of selected surfactants, commercial detergents, and oxidizing agents on lipase stability were studied in a preliminary evaluation for its further usage in the industrial environment. Partially purified lipase has shown good stability in presence of surfactants, commercial detergents, and oxidizing agents. Washing efficiency has been found to be enhanced while using lipase with 0.5% nonionic detergent than the anioinic detergent. The wash performance using 0.5% wheel with 40 U lipase at 40°C in 45 min results in maximum oil removal (62% from the soiled cotton fabric. Hence, the present study opens the new era in enzyme-based detergent sector for formulation of chemical-free detergent using alkaline bacterial lipase.

  19. Structure of product-bound SMG1 lipase: active site gating implications.

    Science.gov (United States)

    Guo, Shaohua; Xu, Jinxin; Pavlidis, Ioannis V; Lan, Dongming; Bornscheuer, Uwe T; Liu, Jinsong; Wang, Yonghua

    2015-12-01

    Monoacylglycerol and diacylglycerol lipases are industrially interesting enzymes, due to the health benefits that arise from the consumption of diglycerides compared to the traditional triglyceride oils. Most lipases possess an α-helix (lid) directly over the catalytic pocket which regulates the activity of the enzyme. Generally, lipases exist in active and inactive conformations, depending on the positioning of this lid subdomain. However, lipase SMG1, a monoacylglycerol and diacylglycerol specific lipase, has an atypical activation mechanism. In the present study we were able to prove by crystallography, in silico analysis and activity tests that only two positions, residues 102 and 278, are responsible for a gating mechanism that regulates the active and inactive states of the lipase, and that no significant structural changes take place during activation except for oxyanion hole formation. The elucidation of the gating effect provided data enabling the rational design of improved lipases with 6-fold increase in the hydrolytic activity toward diacylglycerols, just by providing additional substrate stabilization with a single mutation (F278N or F278T). Due to the conservation of F278 among the monoacylglycerol and diacylglycerol lipases in the Rhizomucor miehei lipase-like family, the gating mechanism described herein might represent a general mechanism applicable to other monoacylglycerol and diacylglycerol lipases as well. Database: Structural data are available in the Protein Data Bank under the accession numbers 4ZRE (F278D mutant) and 4ZRD (F278N mutant). PMID:26365206

  20. NEW LIPASE-PRODUCERS MICROORGANISMS FROM PERUVIAN AMAZONIA WHICH HYDROLYZE PALM OIL AND DERIVATIVES

    Directory of Open Access Journals (Sweden)

    Roxana Trujillo

    2014-04-01

    Full Text Available Two yeasts: Cryptococcus uchicensis TMY9 and Pichia uchicensis TMY10 and one fungus Verticillium tingalensis TMFMB are described for the first time as lipase producer microorganisms. The strains have been isolated after an ecological screening in a palm oil industry. The yeasts- C. uchicensis and Pichia uchicensis - mainly produce extracellular lipases as active as those produced by traditional lipase producing microorganisms. The extracellular lipases are active in the hydrolysis of crude palm oil and its industrial derivatives. Contrarily in the isolated fungus, the lipase mainly remains bonded to biomass. In all cases, greater hydrolytic activities are observed in the hydrolysis of palm olein and super-olein than with saturated substrates as stearine. P. uchicensis lipase shows moderated selectivity versus saturated acid triglycerides compared to substrates with high proportion of oleic acid (olein or superolein. The opposite behavior is observed with C. uchicensis and fungal lipases. P. uchicensis produces a more active crude lipase than C. uchicensis with lower biomass production. The kinetic runs performed with crude yeast lipases suggest a three steps mechanism where the high penetration of lipase in the fat gouts favors the hydrolysis.

  1. Uninephrectomy in rats on a fixed food intake results in adipose tissue lipolysis implicating spleen cytokines.

    Directory of Open Access Journals (Sweden)

    Denis eArsenijevic

    2015-07-01

    Full Text Available The role of mild kidney dysfunction in altering lipid metabolism and promoting inflammation was investigated in uninephrectomized rats (UniNX compared to Sham-operated controls rats. The impact of UniNX was studied 1, 2 and 4 weeks after UniNX under mild food restriction at 90% of ad libitum intake to ensure the same caloric intake in both groups.UniNX resulted in the reduction of fat pad weight. UniNX was associated with increased circulating levels of beta-hydroxybutyrate and glycerol, as well as increased fat pad mRNA of hormone sensitive lipase and adipose triglyceride lipase, suggesting enhanced lipolysis. No decrease in fat pad lipogenesis as assessed by fatty acid synthase activity was observed.Circulating hormones known to regulate lipolysis such as leptin, T3, ghrelin, insulin, corticosterone, angiotensin 1 and angiotensin 2 were not different between the two groups. In contrast, a select group of circulating lipolytic cytokines, including interferon-gamma and granulocyte macrophage–colony stimulating factor, were increased after UniNX. These cytokines levels were elevated in the spleen, but decreased in the kidney, liver and fat pads. This could be explained by anti-inflammatory factors SIRT1, a member of the sirtuins, and the farnesoid x receptor, which were decreased in the spleen but elevated in the kidney, liver and fat pads (inguinal and epididymal. Our study suggests that UniNX induces adipose tissue lipolysis in response to increased levels of a subset of lipolytic cytokines of splenic origin.

  2. An insight on acyl migration in solvent-free ethanolysis of model triglycerides using Novozym 435.

    Science.gov (United States)

    Sánchez, Daniel Alberto; Tonetto, Gabriela Marta; Ferreira, María Luján

    2016-02-20

    In this work, the ethanolysis of triglycerides catalyzed by immobilized lipase was studied, focusing on the secondary reaction of acyl migration. The catalytic tests were performed in a solvent-free reaction medium using Novozym 435 as biocatalyst. The selected experimental variables were biocatalyst loading (5-20mg), reaction time (30-90min), and chain length of the fatty acids in triglycerides with and without unsaturation (short (triacetin), medium (tricaprylin) and long (tripalmitin/triolein)). The formation of 2-monoglyceride by ethanolysis of triglycerides was favored by long reaction times and large biocatalyst loading with saturated short- to medium-chain triglycerides. In the case of long-chain triglycerides, the formation of this monoglyceride was widely limited by acyl migration. In turn, acyl migration increased the yield of ethyl esters and minimized the content of monoglycerides and diglycerides. Thus, the enzymatic synthesis of biodiesel was favored by long-chain triglycerides (which favor the acyl migration), long reaction times and large biocatalyst loading. The conversion of acylglycerides made from long-chain fatty acids with unsaturation was relatively low due to limitations in their access to the active site of the lipase. PMID:26795690

  3. Local and systemic effects of visceral and perivascular adipose tissue

    NARCIS (Netherlands)

    Verhagen, S.N.

    2012-01-01

    Rather than being solely a storage depot for triglycerides, adipose tissue is able to secrete pro- and anti-inflammatory cytokines and adipokines. A state of low grade inflammation associated with excess adipose tissue is involved in the increase in the incidences of atherosclerotic diseases and typ

  4. Pancreatic beta-cell lipotoxicity induced by overexpression of hormone-sensitive lipase

    DEFF Research Database (Denmark)

    Winzell, Maria Sörhede; Svensson, Håkan; Enerbäck, Sven;

    2003-01-01

    Lipid perturbations associated with triglyceride overstorage in beta-cells impair insulin secretion, a process termed lipotoxicity. To assess the role of hormone-sensitive lipase, which is expressed and enzymatically active in beta-cells, in the development of lipotoxicity, we generated transgenic...... mice overexpressing hormone-sensitive lipase specifically in beta-cells. Transgenic mice developed glucose intolerance and severely blunted glucose-stimulated insulin secretion when challenged with a high-fat diet. As expected, both lipase activity and forskolin-stimulated lipolysis was increased...... results highlight the importance of mobilization of the islet triglyceride pool in the development of beta-cell lipotoxicity. We propose that hormone-sensitive lipase is involved in mediating beta-cell lipotoxicity by providing ligands for peroxisome proliferator-activated receptors and other lipid...

  5. Testosterone affects hormone-sensitive lipase (HSL) activity and lipid metabolism in the left ventricle.

    Science.gov (United States)

    Langfort, Jozef; Jagsz, Slawomir; Dobrzyn, Pawel; Brzezinska, Zofia; Klapcinska, Barbara; Galbo, Henrik; Gorski, Jan

    2010-09-01

    Fatty acids, which are the major cardiac fuel, are derived from lipid droplets stored in cardiomyocytes, among other sources. The heart expresses hormone-sensitive lipase (HSL), which regulates triglycerides (TG) breakdown, and the enzyme is under hormonal control. Evidence obtained from adipose tissue suggests that testosterone regulates HSL activity. To test whether this is also true in the heart, we measured HSL activity in the left ventricle of sedentary male rats that had been treated with testosterone supplementation or orchidectomy with or without testosterone substitution. Left ventricle HSL activity against TG was significantly elevated in intact rats supplemented with testosterone. HSL activity against both TG and diacylglyceride was reduced by orchidectomy, whereas testosterone replacement fully reversed this effect. Moreover, testosterone increased left ventricle free fatty acid levels, caused an inhibitory effect on carbohydrate metabolism in the heart, and elevated left ventricular phosphocreatine and ATP levels as compared to control rats. These data indicate that testosterone is involved in cardiac HSL activity regulation which, in turn, may affect cardiac lipid and carbohydrate metabolism.

  6. m-DOPA addition in MAPLE immobilization of lipase for biosensor applications

    OpenAIRE

    Valeria Califano; Giovanni Ausanio; Francesco Bloisi; Antonio Aronne; Luciano R.M. Vicari; Libera Nasti

    2015-01-01

    Matrix Assisted Pulsed Laser Evaporation (MAPLE) is a thin film deposition technique which uses a pulsed laser beam impinging, inside a high vacuum chamber, on a frozen target containing the guest molecules in a volatile matrix to induce fast “evaporation” of the matrix, and ejection of the guest molecules. Lipase, an enzyme acting as a catalyst in hydrolysis of lipids, is widely used in biosensors for detection of triglycerides in blood serum. A key action to this purpose is lipase immobiliz...

  7. Influences of apolipoprotein E on soluble and heparin-immobilized hepatic lipase

    International Nuclear Information System (INIS)

    The effect of human apolipoprotein E (apoE), either alone or in combination with apoC, on the lipolysis of a radiolabeled triglyceride emulsion was studied with hepatic lipase in solution and immobilized on heparin-Sepharose. The soluble hepatic lipase was inhibited, whereas the heparin-immobilized lipase was stimulated by apoE. This stimulation was attenuated by combining apoE with either apoC-II or C-III. The heparin-immobilized lipase demonstrated much less lipolysis of the zwitterionic phosphatidylcholine-stabilized triglyceride emulsion than did the soluble enzyme. This difference was less when the emulsion was stabilized by a nonionic detergent. apoE inhibited lipase activity when assayed under conditions (0.4 M NaCl) of bound enzyme and unbound substrate. Increasing the emulsion apoE content beyond optimum inhibited lipolysis by the immobilized enzyme. Kinetic analysis of phosphatidylcholine-stabilized triglyceride emulsions revealed a significant decrease in immobilized enzyme K/sub m/ and an increase in V/sub max/ when the emulsion was supplemented with apoE. Distributing the immobilized lipase in clustered aggregates produced more lipolysis than when the same enzyme content was uniformly bound

  8. Lysosomal acid lipase deficiency in rats: Lipid analyses and lipase activities in liver and spleen

    International Nuclear Information System (INIS)

    We report the biological characterization of an animal model of a genetic lipid storage disease analogous to human Wolman's disease. Affected rats accumulated cholesteryl esters (13.3-fold), free cholesterol (2.8-fold), and triglycerides (5.4-fold) in the liver, as well as cholesteryl esters (2.5-fold) and free cholesterol (1.33-fold) in the spleen. Triglycerides did not accumulate, and the levels actually decreased in the spleen. Analysis of the fatty acid composition of the cholesteryl esters and triglycerides showed high percentages of linoleic acid (18:2) and arachidonic acid (20:4) in both organs, especially in the liver. No accumulation of phospholipids, neutral glycosphingolipids, or gangliosides was found in the affected rats. Acid lipase activity for [14C]triolein, [14C]cholesteryl oleate, and 4-methyl-umbelliferyl oleate was deficient in both the liver and spleen of affected rats. Lipase activity at neutral pH was normal in both liver and spleen. Heterozygous rats showed intermediate utilization of these substrates in both organs at levels between those for affected rats and those for normal controls, although they did not accumulate any lipids. These data suggest that these rats represent an animal counterpart of Wolman's disease in humans

  9. Bacterial lipases for biotechnological applications

    NARCIS (Netherlands)

    Jaeger, Karl-Erich; Schneidinger, Bernd; Rosenau, Frank; Werner, Michael; Lang, Dietmar; Dijkstra, Bauke W.; Schimossek, Klaus; Zonta, Albin; Reetz, Manfred T.

    1997-01-01

    Lipase genes originating from the Gram-negative bacteria Serrutiu marcescens and Pseudomonus urruginosa were cloned. S. marcescens lipase was overexpressed in Escherichia coli yielding inclusion bodies which were purified and finally refolded to give enzymatically active lipase. The lipase operon of

  10. Interaction of rat hormone-sensitive lipase with adipocyte lipid-binding protein

    OpenAIRE

    Shen, Wen-Jun; Sridhar, Kunju; Bernlohr, David A.; Fredric B Kraemer

    1999-01-01

    Hormone-sensitive lipase (HSL) is a cytosolic neutral lipase that functions as the rate-limiting enzyme for the mobilization of free fatty acids in adipose tissue. By using the yeast two-hybrid system to examine the potential interaction of HSL with other cellular proteins, evidence is provided to demonstrate a direct interaction of HSL with adipocyte lipid-binding protein (ALBP), a member of the family of intracellular lipid-binding proteins that binds fatty acids, retinoids, and other hydro...

  11. High-throughput virtual screening with e-pharmacophore and molecular simulations study in the designing of pancreatic lipase inhibitors

    Directory of Open Access Journals (Sweden)

    Veeramachaneni GK

    2015-08-01

    Full Text Available Ganesh Kumar Veeramachaneni, K Kranthi Raj, Leela Madhuri Chalasani, Jayakumar Singh Bondili, Venkateswara Rao Talluri Department of Biotechnology, K L University, Guntur, India Background: Obesity is a progressive metabolic disorder in the current world population, and is characterized by the excess deposition of fat in the adipose tissue. Pancreatic lipase is one of the key enzymes in the hydrolysis of triglycerides into monoglycerides and free fatty acids, and is thus considered a promising target for the treatment of obesity. The present drugs used for treating obesity do not give satisfactory results, and on prolonged usage result in severe side effects. In view of the drastic increase in the obese population day-to-day, there is a greater need to discover new drugs with lesser side effects.Materials and methods: High-throughput virtual screening combined with e-pharmacophore screening and ADME (absorption, distribution, metabolism, and excretion and PAINS (pan-assay interference compounds filters were applied to screen out the ligand molecules from the ZINC natural molecule database. The screened molecules were subjected to Glide XP docking to study the molecular interactions broadly. Further, molecular dynamic simulations were used to validate the stability of the enzyme–ligand complexes. Finally, the molecules with better results were optimized for in vitro testing.Results: The screening protocols identified eight hits from the natural molecule database, which were further filtered through pharmacological filters. The final four hits were subjected to extra precision docking, and the complexes were finally studied with molecular dynamic simulations. The results pointed to the zinc 85893731 molecule as the most stable in the binding pocket, producing consistent H-bond interaction with Ser152 (G=-7.18. The optimized lead molecule exhibited good docking score, better fit, and improved ADME profile.Conclusion: The present study specifies

  12. Acid lipase from Candida viswanathii: production, biochemical properties, and potential application.

    Science.gov (United States)

    de Almeida, Alex Fernando; Tauk-Tornisielo, Sâmia Maria; Carmona, Eleonora Cano

    2013-01-01

    Influences of environmental variables and emulsifiers on lipase production of a Candida viswanathii strain were investigated. The highest lipase activity (101.1 U) was observed at 210 rpm, pH 6.0, and 27.5°C. Other fermentation parameters analyzed showed considerable rates of biomass yield (Y L/S = 1.381 g/g), lipase yield (Y L/S = 6.892 U/g), and biomass productivity (P X = 0.282 g/h). Addition of soybean lecithin increased lipase production in 1.45-fold, presenting lipase yield (Y L/S ) of 10.061 U/g. Crude lipase presented optimal activity at acid pH of 3.5, suggesting a new lipolytic enzyme for this genus and yeast in general. In addition, crude lipase presented high stability in acid conditions and temperature between 40 and 45°C, after 24 h of incubation in these temperatures. Lipase remained active in the presence of organic solvents maintaining above 80% activity in DMSO, methanol, acetonitrile, ethanol, acetone, 1-propanol, isopropanol, and 2-propanol. Effectiveness for the hydrolysis of a wide range of natural triglycerides suggests that this new acid lipase has high potential application in the oleochemical and food industries for hydrolysis and/or modification of triacylglycerols to improve the nutritional properties. PMID:24350270

  13. Acid lipase from Candida viswanathii: production, biochemical properties, and potential application.

    Science.gov (United States)

    de Almeida, Alex Fernando; Tauk-Tornisielo, Sâmia Maria; Carmona, Eleonora Cano

    2013-01-01

    Influences of environmental variables and emulsifiers on lipase production of a Candida viswanathii strain were investigated. The highest lipase activity (101.1 U) was observed at 210 rpm, pH 6.0, and 27.5°C. Other fermentation parameters analyzed showed considerable rates of biomass yield (Y L/S = 1.381 g/g), lipase yield (Y L/S = 6.892 U/g), and biomass productivity (P X = 0.282 g/h). Addition of soybean lecithin increased lipase production in 1.45-fold, presenting lipase yield (Y L/S ) of 10.061 U/g. Crude lipase presented optimal activity at acid pH of 3.5, suggesting a new lipolytic enzyme for this genus and yeast in general. In addition, crude lipase presented high stability in acid conditions and temperature between 40 and 45°C, after 24 h of incubation in these temperatures. Lipase remained active in the presence of organic solvents maintaining above 80% activity in DMSO, methanol, acetonitrile, ethanol, acetone, 1-propanol, isopropanol, and 2-propanol. Effectiveness for the hydrolysis of a wide range of natural triglycerides suggests that this new acid lipase has high potential application in the oleochemical and food industries for hydrolysis and/or modification of triacylglycerols to improve the nutritional properties.

  14. Strategies to Characterize Fungal Lipases for Applications in Medicine and Dairy Industry

    Directory of Open Access Journals (Sweden)

    Subash C. B. Gopinath

    2013-01-01

    Full Text Available Lipases are water-soluble enzymes that act on insoluble substrates and catalyze the hydrolysis of long-chain triglycerides. Lipases play a vital role in the food, detergent, chemical, and pharmaceutical industries. In the past, fungal lipases gained significant attention in the industries due to their substrate specificity and stability under varied chemical and physical conditions. Fungal enzymes are extracellular in nature, and they can be extracted easily, which significantly reduces the cost and makes this source preferable over bacteria. Soil contaminated with spillage from the products of oil and dairy harbors fungal species, which have the potential to secrete lipases to degrade fats and oils. Herein, the strategies involved in the characterization of fungal lipases, capable of degrading fatty substances, are narrated with a focus on further applications.

  15. Les lipases sont des hydrolases atypiques : principales caractéristiques et applications

    Directory of Open Access Journals (Sweden)

    Fickers P.

    2008-01-01

    Full Text Available ipases are atypical hydrolases: principal characteristics and applications. Due to their kinetic and substrate specificities, triacylglycerol acyl-hydrolases or lipases are atypical enzymes. In function of their microenvironment, lipases are able to act as hydrolases in aqueous solution or as biocatalysts in organic synthesis. As hydrolases, they are responsible of the triglycerids catabolism into fatty acids and glycerol. In many organisms, this reaction plays a major role in the fat and lipid metabolism. In addition, lipases are also able to hydrolyse phospholipids and cholesterol esters. In organic solvent, lipases could catalyse reactions such as esterifications, acidolysis or alcoolysis with enantio-, regio- and chimioselectivity. Lipases form a mixed class of enzyme due to their animal, vegetal or microbial origins. All those properties led to the development of many applications in the food and chemical industries but also in the medical and therapeutic field.

  16. Lipase-catalyzed biodiesel synthesis with different acyl acceptors

    Directory of Open Access Journals (Sweden)

    Ognjanović Nevena D.

    2008-01-01

    Full Text Available Biodiesel is an alternative fuel for diesel engine that is environmentally acceptable. Conventionally, biodiesel is produced by transesterification of triglycerides and short alcohols in the presence of an acid or an alkaline catalyst. There are several problems associated with this kind of production that can be resolved by using lipase as the biocatalyst. The aim of the present work was to investigate novel acyl acceptors for biodiesel production. 2-Propanol and n-butanol have a less negative effect on lipase stability, and they also improve low temperature properties of the fuel. However, excess alcohol leads to inactivation of the enzyme, and glycerol, a major byproduct, can block the immobilized enzyme, resulting in low enzymatic activity. This problem was solved by using methyl acetate as acyl acceptor. Triacetylglycerol is produced instead of glycerol, and it has no negative effect on the activity of the lipase.

  17. Serum lipoprotein lipase mass: Clinical significance of its measurement

    OpenAIRE

    Kobayashi, Junji; Nohara, Atsushi; Kawashiri, Masaaki; Inazu, Akihiro; Koizumi, Junji; Nakajima, Katsuyuki; Mabuchi, Hiroshi

    2007-01-01

    Lipoprotein lipase (LPL) is a lipolytic enzyme involved in catalyzing hydrolysis of triglycerides (TG) in chylomicrons and very low-density lipoprotein (VLDL) particles. Over the last decade, increasing attention has been paid to the clinical significance of measuring serum LPL protein mass without heparin injection to the study subjects. In earlier studies, this marker was utilized to classify LPL deficient subjects, which is an extremely rare metabolic disorder with a frequency of one in on...

  18. Lipoprotein lipase links dietary fat to solid tumor cell proliferation

    OpenAIRE

    Kuemmerle, Nancy B.; Rysman, Evelien; Lombardo, Portia S.; Flanagan, Alison J.; Lipe, Brea C.; Wells, Wendy A.; Pettus, Jason R.; Froehlich, Heather M.; Memoli, Vincent A.; Morganelli, Peter M.; Swinnen, Johannes V.; Timmerman, Luika A.; Chaychi, Leila; Fricano, Catherine J.; Eisenberg, Burton L.

    2011-01-01

    Many types of cancer cells require a supply of fatty acids (FA) for growth and survival, and interrupting de novo FA synthesis in model systems causes potent anticancer effects. We hypothesized that, in addition to synthesis, cancer cells may obtain pre-formed, diet-derived fatty acids by uptake from the bloodstream. This would require hydrolytic release of FA from triglyceride in circulating lipoprotein particles by the secreted enzyme lipoprotein lipase (LPL), and the expression of CD36, th...

  19. Alterations in Adipose Tissue during Critical Illness: An Adaptive and Protective Response?

    OpenAIRE

    Langouche, Lies; Vander Perre, Sarah; Thiessen, Steven; Gunst, Jan; Hermans, Greet; D'Hoore, André; Kola, Blerina; Korbonits, Márta; Van den Berghe, Greet

    2010-01-01

    Rationale: Critical illness is characterized by lean tissue wasting, whereas adipose tissue is preserved. Overweight and obese critically ill patients may have a lower risk of death than lean patients, suggestive of a protective role for adipose tissue during illness. Objectives: To investigate whether adipose tissue could protectively respond to critical illness by storing potentially toxic metabolites, such as excess circulating glucose and triglycerides. Methods: We studied adipose tissue ...

  20. Cloning and functional characterization of the 5' regulatory region of ovine Hormone Sensitive Lipase (HSL) gene.

    Science.gov (United States)

    Lampidonis, Antonis D; Stravopodis, Dimitrios J; Voutsinas, Gerassimos E; Messini-Nikolaki, Niki; Stefos, George C; Margaritis, Lukas H; Argyrokastritis, Alexandros; Bizelis, Iosif; Rogdakis, Emmanuel

    2008-12-31

    Hormone Sensitive Lipase (HSL) catalyzes the rate-limiting step in the mobilization of fatty acids from adipose tissue, thus determining the supply of energy substrates in the body. HSL enzymatic activity is increased by adrenergic agonists, such as catecholamines and glucagons, which induce cyclic AMP (cAMP) intracellular production, subsequently followed by the activation of Protein Kinase A (PKA) and its downstream signaling cascade reactions. HSL constitutes the critical enzyme in the modulation of lipid stores and the only component being subjected to hormonal control in terms of the recently identified Adipose Triglyceride Lipase (ATGL). In order to acquire detailed knowledge with regard to the mechanisms regulating ovine HSL (ovHSL) gene transcription activity, we initially isolated and cloned the 5' proximal and distal promoter regions through a genome walking approach, with the utilization of the already characterized ovHSL cDNAs. As evinced by BLAST analysis and a multiple alignment procedure, the isolated genomic fragment of 2.744 kb appeared to contain the already specified 5'-untranslated region (5'-UTR), which was interrupted by a relatively large intron of 1.448 kb. Regarding the upstream remaining part of 1.224 kb, it was demonstrated to represent a TATA-less promoter area, harboring several cis-regulatory elements that could be putatively recognized by relatively more general transcription factors, mainly including Stimulating protein 1 (Sp1), CCAAT-box Binding Factors (CBFs), Activator Protein 2 (AP2) and Glucocorticoid Receptor (GR), as well as other cis-acting regions denominated as Insulin Response Element (IRE), Glucose Response Element (GRE), Fat Specific Element (FSE) and cAMP Response Element (CRE), which could likely function in a nourishment (i.e. glucose)-/hormone-dependent fashion. When different genomic fragments were directionally (5' to 3') cloned into a suitable reporter vector upstream of a promoter-less luciferase gene and

  1. Adipose tissue dysfunction and hypertriglyceridemia : mechanisms and management

    NARCIS (Netherlands)

    van de Woestijne, A. P.; Monajemi, H.; Kalkhoven, E.; Visseren, F. L. J.

    2011-01-01

    Elevated plasma triglyceride levels, as often seen in obese subjects, are independently associated with an increased risk of cardiovascular diseases. By secreting adipokines (such as adiponectin and leptin) and other proteins (such as lipoprotein lipase and cholesteryl ester transferase protein), ad

  2. Triglycerides in the human kidney cortex: relationship with body size.

    Directory of Open Access Journals (Sweden)

    Ion Alexandru Bobulescu

    Full Text Available Obesity is associated with increased risk for kidney disease and uric acid nephrolithiasis, but the pathophysiological mechanisms underpinning these associations are incompletely understood. Animal experiments have suggested that renal lipid accumulation and lipotoxicity may play a role, but whether lipid accumulation occurs in humans with increasing body mass index (BMI is unknown. The association between obesity and abnormal triglyceride accumulation in non-adipose tissues (steatosis has been described in the liver, heart, skeletal muscle and pancreas, but not in the human kidney. We used a quantitative biochemical assay to quantify triglyceride in normal kidney cortex samples from 54 patients undergoing nephrectomy for localized renal cell carcinoma. In subsets of the study population we evaluated the localization of lipid droplets by Oil Red O staining and measured 16 common ceramide species by mass spectrometry. There was a positive correlation between kidney cortex trigyceride content and BMI (Spearman R = 0.27, P = 0.04. Lipid droplets detectable by optical microscopy had a sporadic distribution but were generally more prevalent in individuals with higher BMI, with predominant localization in proximal tubule cells and to a lesser extent in glomeruli. Total ceramide content was inversely correlated with triglycerides. We postulate that obesity is associated with abnormal triglyceride accumulation (steatosis in the human kidney. In turn, steatosis and lipotoxicity may contribute to the pathogenesis of obesity-associated kidney disease and nephrolithiasis.

  3. Autocrine function of aldehyde dehydrogenase 1 as a determinant of diet- and sex-specific differences in visceral adiposity.

    Science.gov (United States)

    Yasmeen, Rumana; Reichert, Barbara; Deiuliis, Jeffrey; Yang, Fangping; Lynch, Alisha; Meyers, Joseph; Sharlach, Molly; Shin, Sangsu; Volz, Katharina S; Green, Kari B; Lee, Kichoon; Alder, Hansjuerg; Duester, Gregg; Zechner, Rudolf; Rajagopalan, Sanjay; Ziouzenkova, Ouliana

    2013-01-01

    Mechanisms for sex- and depot-specific fat formation are unclear. We investigated the role of retinoic acid (RA) production by aldehyde dehydrogenase 1 (Aldh1a1, -a2, and -a3), the major RA-producing enzymes, on sex-specific fat depot formation. Female Aldh1a1(-/-) mice, but not males, were resistant to high-fat (HF) diet-induced visceral adipose formation, whereas subcutaneous fat was reduced similarly in both groups. Sexual dimorphism in visceral fat (VF) was attributable to elevated adipose triglyceride lipase (Atgl) protein expression localized in clusters of multilocular uncoupling protein 1 (Ucp1)-positive cells in female Aldh1a1(-/-) mice compared with males. Estrogen decreased Aldh1a3 expression, limiting conversion of retinaldehyde (Rald) to RA. Rald effectively induced Atgl levels via nongenomic mechanisms, demonstrating indirect regulation by estrogen. Experiments in transgenic mice expressing an RA receptor response element (RARE-lacZ) revealed HF diet-induced RARE activation in VF of females but not males. In humans, stromal cells isolated from VF of obese subjects also expressed higher levels of Aldh1 enzymes compared with lean subjects. Our data suggest that an HF diet mediates VF formation through a sex-specific autocrine Aldh1 switch, in which Rald-mediated lipolysis in Ucp1-positive visceral adipocytes is replaced by RA-mediated lipid accumulation. Our data suggest that Aldh1 is a potential target for sex-specific antiobesity therapy. PMID:22933113

  4. Triglyceride-Rich Lipoproteins and Remnants: Targets for Therapy?

    Science.gov (United States)

    Dallinga-Thie, Geesje M; Kroon, Jeffrey; Borén, Jan; Chapman, M John

    2016-07-01

    It is now evident that elevated circulating levels of triglycerides in the non-fasting state, a marker for triglyceride (TG)-rich remnant particles, are associated with increased risk of premature cardiovascular disease (CVD). Recent findings from basic and clinical studies have begun to elucidate the mechanisms that contribute to the atherogenicity of these apoB-containing particles. Here, we review current knowledge of the formation, intravascular remodelling and catabolism of TG-rich lipoproteins and highlight (i) the pivotal players involved in this process, including lipoprotein lipase, glycosylphosphatidylinositol HDL binding protein 1 (GPIHBP1), apolipoprotein (apo) C-II, apoC-III, angiopoietin-like protein (ANGPTL) 3, 4 and 8, apoA-V and cholesteryl ester transfer protein; (ii) key determinants of triglyceride (TG) levels and notably rates of production of very-low-density lipoprotein 1 (VLDL1) particles; and (iii) the mechanisms which underlie the atherogenicity of remnant particles. Finally, we emphasise the polygenic nature of moderate hypertriglyceridemia and briefly discuss modalities for its clinical management. Several new therapeutic strategies to attenuate hypertriglyceridemia have appeared recently, among which those targeted to apoC-III appear to hold considerable promise. PMID:27216847

  5. Regulation of lipoprotein lipase in primary cultures of isolated human adipocytes.

    OpenAIRE

    Kern, P A; Marshall, S; Eckel, R H

    1985-01-01

    To study the regulation of adipose tissue lipoprotein lipase (LPL) in human adipocytes, omental adipose tissue was obtained from healthy subjects and digested in collagenase. The isolated adipocytes thus obtained were suspended in Medium 199 and cultured at 37 degrees C. Cell viability was demonstrated in adipocytes cultured for up to 72 h by constancy of cell number, cell size, trypan-blue exclusion, and specific 125I-insulin binding. In addition, chloroquine induced an increase in cell-asso...

  6. Acid Lipase from Candida viswanathii: Production, Biochemical Properties, and Potential Application

    Directory of Open Access Journals (Sweden)

    Alex Fernando de Almeida

    2013-01-01

    Full Text Available Influences of environmental variables and emulsifiers on lipase production of a Candida viswanathii strain were investigated. The highest lipase activity (101.1 U was observed at 210 rpm, pH 6.0, and 27.5°C. Other fermentation parameters analyzed showed considerable rates of biomass yield ( g/h. Addition of soybean lecithin increased lipase production in 1.45-fold, presenting lipase yield ( of 10.061 U/g. Crude lipase presented optimal activity at acid pH of 3.5, suggesting a new lipolytic enzyme for this genus and yeast in general. In addition, crude lipase presented high stability in acid conditions and temperature between 40 and 45°C, after 24 h of incubation in these temperatures. Lipase remained active in the presence of organic solvents maintaining above 80% activity in DMSO, methanol, acetonitrile, ethanol, acetone, 1-propanol, isopropanol, and 2-propanol. Effectiveness for the hydrolysis of a wide range of natural triglycerides suggests that this new acid lipase has high potential application in the oleochemical and food industries for hydrolysis and/or modification of triacylglycerols to improve the nutritional properties.

  7. Assaying lipase activity from oil palm fruit (Elaeis guineensis Jacq.) mesocarp.

    Science.gov (United States)

    Ngando Ebongue, G F; Dhouib, R; Carrière, F; Amvam Zollo, P-H; Arondel, V

    2006-10-01

    The mesocarp of mature oil palm fruit undergoes intensive triglycerides hydrolysis upon abscission and bruising. This generates such a high amount of free fatty acids that the oil might become unfit for human consumption without appropriate refining. The lipase (EC 3.1.1.3) involved in the breakdown of the oil is not stable after homogenization of the tissue in aqueous buffers. In this study, we have devised a solvent-based procedure that allowed us to obtain fractions with stable lipase activity. Using these fractions, we have determined the optimal conditions for assaying mesocarp lipase activity. The activity was highest at a temperature of 35 degrees C and a pH of 9. The lipase was found to be strictly calcium dependent. The specific activity of the lipase measured in optimal conditions was found to be 33 mumol fatty acids released min(-1) mg(-1) protein using olive oil as substrate. The mesocarp contains about 190 U of lipase g(-1) fresh weight. This activity was found to be inhibited by the lipase inhibitor tetrahydrolipstatin (THL), suggesting that the lipase is a serine hydrolase. PMID:17064925

  8. Gene therapy for genetic lipoprotein lipase deficiency : from promise to practice

    NARCIS (Netherlands)

    Nierman, M C; Rip, J; Twisk, J; Meulenberg, J J M; Kastelein, J J P; Stroes, E S G; Kuivenhoven, J A

    2005-01-01

    Lipoprotein lipase (LPL) deficiency is a rare, hereditary disorder of lipoprotein metabolism characterised by severely increased triglyceride levels, and associated with an increased risk for pancreatitis. Since no adequate treatment modality is available for this disorder, we set out to develop an

  9. Impact of dietary protein on lipid metabolism-related gene expression in porcine adipose tissue

    Directory of Open Access Journals (Sweden)

    Ge Changrong

    2010-01-01

    Full Text Available Abstract Background High dietary protein can reduce fat deposition in animal subcutaneous adipose tissue, but little is known about the mechanism. Methods Sixty Wujin pigs of about 15 kg weight were fed either high protein (HP: 18% or low protein (LP: 14% diets, and slaughtered at body weights of 30, 60 or 100 kg. Bloods were collected to measure serum parameters. Subcutaneous adipose tissues were sampled for determination of adipocyte size, protein content, lipid metabolism-related gene expression, and enzyme activities. Results HP significantly reduced adipocyte size, fat meat percentage and backfat thickness, but significantly increased daily gain, lean meat percentage and loin eye area at 60 and 100 kg. Serum free fatty acid and triglyceride concentrations in the HP group were significantly higher than in the LP group. Serum glucose and insulin concentrations were not significantly affected by dietary protein at any body weight. HP significantly reduced gene expression of acetyl CoA carboxylase (ACC, fatty acid synthase (FAS and sterol regulatory element binding protein 1c (SREBP-1c at 60 kg and 100 kg; however, the mRNA level and enzyme activity of FAS were increased at 30 kg. HP promoted gene and protein expression and enzyme activities of lipoprotein lipase (LPL, carmitine palmtoyltransferase-1B (CPT-1B, peroxisome proliferator-activated receptor γ (PPARγ and adipocyte-fatty acid binding proteins (A-FABP at 60 kg, but reduced their expression at 100 kg. Gene expression and enzyme activity of hormone sensitive lipase (HSL was reduced markedly at 60 kg but increased at 100 kg by the high dietary protein. Levels of mRNA, enzyme activities and protein expression of ACC, FAS, SREBP-1c and PPARγ in both LP and HP groups increased with increasing body weight. However, gene and protein expression levels/enzyme activities of LPL, CPT-1B, A-FABP and HSL in both groups were higher at 60 kg than at 30 and 100 kg. Conclusion Fat deposition in Wujin

  10. Enzymes involved in triglyceride hydrolysis.

    Science.gov (United States)

    Taskinen, M R; Kuusi, T

    1987-08-01

    The lipolytic enzymes LPL and HL play important roles in the metabolism of lipoproteins and participate in lipoprotein interconversions. LPL was originally recognized to be the key enzyme in the hydrolysis of chylomicrons and triglyceride, but it also turned out to be one determinant of HDL concentration in plasma. When LPL activity is high, chylomicrons and VLDL are rapidly removed from circulation and a concomitant rise of the HDL2 occurs. In contrast, low LPL activity impedes the removal of triglyceride-rich particles, resulting in the elevation of serum triglycerides and a decrease of HDL (HDL2). Concordant changes of this kind in LPL and HDL2 are induced by many physiological and pathological perturbations. Finally, the operation of LPL is also essential for the conversion of VLDL to LDL. This apparently clear-cut role of LPL in lipoprotein interconversions is contrasted with the enigmatic actions of HL. The enzyme was originally thought to participate in the catalyses of chylomicron and VLDL remnants generated in the LPL reaction. However, substantial in vitro and in vivo data indicate that HL is a key enzyme in the degradation of plasma HDL (HDL2) in a manner which opposes LPL. A scheme is presented for the complementary actions of the two enzymes in plasma HDL metabolism. In addition, recent studies have attributed a role to HL in the catabolism of triglyceride-rich lipoproteins, particularly those containing apo E. However, this function becomes clinically important only under conditions where the capacity of the LPL-mediated removal system is exceeded. Such a situation may arise when the input of triglyceride-rich particles (chylomicrons and/or VLDL) is excessive or LPL activity is decreased or absent.

  11. High-throughput screening method for lipases/esterases.

    Science.gov (United States)

    Mateos-Díaz, Eduardo; Rodríguez, Jorge Alberto; de Los Ángeles Camacho-Ruiz, María; Mateos-Díaz, Juan Carlos

    2012-01-01

    High-throughput screening (HTS) methods for lipases and esterases are generally performed by using synthetic chromogenic substrates (e.g., p-nitrophenyl, resorufin, and umbelliferyl esters) which may be misleading since they are not their natural substrates (e.g., partially or insoluble triglycerides). In previous works, we have shown that soluble nonchromogenic substrates and p-nitrophenol (as a pH indicator) can be used to quantify the hydrolysis and estimate the substrate selectivity of lipases and esterases from several sources. However, in order to implement a spectrophotometric HTS method using partially or insoluble triglycerides, it is necessary to find particular conditions which allow a quantitative detection of the enzymatic activity. In this work, we used Triton X-100, CHAPS, and N-lauroyl sarcosine as emulsifiers, β-cyclodextrin as a fatty acid captor, and two substrate concentrations, 1 mM of tributyrin (TC4) and 5 mM of trioctanoin (TC8), to improve the test conditions. To demonstrate the utility of this method, we screened 12 enzymes (commercial preparations and culture broth extracts) for the hydrolysis of TC4 and TC8, which are both classical substrates for lipases and esterases (for esterases, only TC4 may be hydrolyzed). Subsequent pH-stat experiments were performed to confirm the preference of substrate hydrolysis with the hydrolases tested. We have shown that this method is very useful for screening a high number of lipases (hydrolysis of TC4 and TC8) or esterases (only hydrolysis of TC4) from wild isolates or variants generated by directed evolution using nonchromogenic triglycerides directly in the test.

  12. Utilization of immobilized lipases as catalysts in the transesterification of non-edible vegetable oils with ethanol

    OpenAIRE

    P. C. Tiosso; A. K. F. Carvalho; H. F. de Castro; F.F. de Moraes; G. M. Zanin

    2014-01-01

    This work reports the use of commercially available immobilized lipase preparations (Novozym® 435 and Lipozyme TL IM, both from Novozymes, and Lipase PS IM from Amano) as catalysts in the transesterification reaction of different alkyl-chain triglycerides with ethanol. The ethanolysis of native oils from Brazilian Amazon plants andiroba (Carapa guianensis), babassu (Orbignya sp.), jatropa (Jatropha curcas), and palm (Elaeis sp.) was studied in a solvent-free system. In a typical reaction, the...

  13. Therapeutic Targets of Triglyceride Metabolism as Informed by Human Genetics.

    Science.gov (United States)

    Bauer, Robert C; Khetarpal, Sumeet A; Hand, Nicholas J; Rader, Daniel J

    2016-04-01

    Human genetics has contributed to the development of multiple drugs to treat hyperlipidemia and coronary artery disease (CAD), most recently including antibodies targeting PCSK9 to reduce LDL cholesterol. Despite these successes, a large burden of CAD remains. Genetic and epidemiological studies have suggested that circulating triglyceride (TG)-rich lipoproteins (TRLs) are a causal risk factor for CAD, presenting an opportunity for novel therapeutic strategies. We discuss recent unbiased human genetics testing, including genome-wide association studies (GWAS) and whole-genome or -exome sequencing, that have identified the lipoprotein lipase (LPL) and hepatic lipogenesis pathways as important mechanisms in the regulation of circulating TRLs. Further strengthening the causal relationship between TRLs and CAD, findings such as these may provide novel targets for much-needed potential therapeutic interventions. PMID:26988439

  14. A Sequence Variation (I148M) in PNPLA3 Associated with Nonalcoholic Fatty Liver Disease Disrupts Triglyceride Hydrolysis*

    OpenAIRE

    He, Shaoqing; McPhaul, Christopher; Li, John Zhong; Garuti, Rita; Kinch, Lisa; Nick V Grishin; Cohen, Jonathan C.; Hobbs, Helen H.

    2009-01-01

    Obesity and insulin resistance are associated with deposition of triglycerides in tissues other than adipose tissue. Previously, we showed that a missense mutation (I148M) in PNPLA3 (patatin-like phospholipase domain-containing 3 protein) is associated with increased hepatic triglyceride content in humans. Here we examined the effect of the I148M substitution on the enzymatic activity and cellular location of PNPLA3. Structural modeling predicted that the substitution of methionine for isoleu...

  15. Domain exchange: characterization of a chimeric lipase of hepatic lipase and lipoprotein lipase.

    OpenAIRE

    Wong, H; Davis, R. C.; Nikazy, J; Seebart, K E; Schotz, M C

    1991-01-01

    Hepatic lipase and lipoprotein lipase hydrolyze fatty acids from triacylglycerols and are critical in the metabolism of circulating lipoproteins. The two lipases are similar in size and amino acid sequence but are distinguished by functional differences in substrate preference and cofactor requirement. Presumably, these distinctions result from structural differences in functional domains. To begin localization of these domains, a chimeric lipase was constructed composed of the N-terminal 329...

  16. Characterization of lipase in reversed micelles formulated by Cibacron Blue F-3GA modified Span 85

    DEFF Research Database (Denmark)

    Zhang, Dong Hao; Guo, Zheng; Sun, Yan

    2007-01-01

    that reversed micellar technology could increase the apparent activity of enzymes and even yield superactivity for specific enzymes (6). Lipases are ubiquitous enzymes that could find many important applications (7, 8). The natural substrate of lipases is triglyceride, and the majority of lipases......Sorbitan trioleate (Span 85) modified by Cibacron Blue F-3GA (CB) was prepared and used as an affinity surfactant to formulate a reversed micellar system for Candida rugosa lipase (CRL) solubilization. The system was characterized and evaluated by employing CRL-catalyzed hydrolysis of olive oil...... as a model reaction. The micellar hydrodynamic radius results reflected, to some extent, the redistribution of surfactant and water after enzyme addition, and the correlation between surfactant formulation, water content (W0), micellar size, and enzyme activity. An adequate modification density of CB...

  17. The Inhibition of Lipase and Glucosidase Activities by Acacia Polyphenol

    Directory of Open Access Journals (Sweden)

    Nobutomo Ikarashi

    2011-01-01

    Full Text Available Acacia polyphenol (AP extracted from the bark of the black wattle tree (Acacia mearnsii is rich in unique catechin-like flavan-3-ols, such as robinetinidol and fisetinidol. In an in vitro study, we measured the inhibitory activity of AP on lipase and glucosidase. In addition, we evaluated the effects of AP on absorption of orally administered olive oil, glucose, maltose, sucrose and starch solution in mice. We found that AP concentration-dependently inhibited the activity of lipase, maltase and sucrase with an IC50 of 0.95, 0.22 and 0.60 mg ml−1, respectively. In ICR mice, olive oil was administered orally immediately after oral administration of AP solution, and plasma triglyceride concentration was measured. We found that AP significantly inhibited the rise in plasma triglyceride concentration after olive oil loading. AP also significantly inhibited the rise in plasma glucose concentration after maltose and sucrose loading, and this effect was more potent against maltose. AP also inhibited the rise in plasma glucose concentration after glucose loading and slightly inhibited it after starch loading. Our results suggest that AP inhibits lipase and glucosidase activities, which leads to a reduction in the intestinal absorption of lipids and carbohydrates.

  18. Adequate evaluation of HSL mass and activity in rat adipose tissue in fasting and aging-related obesity.

    Science.gov (United States)

    Tsujita, Takahiro; Sumiyoshi, Maho; Morimoto, Chie; Kameda, Kenji; Okuda, Hiromichi

    2002-04-01

    Adipose tissue is a unique tissue because its mass is readily changed by altering nutritional conditions. Therefore the activity and content of enzyme in the adipose tissue is significantly differed according to the way of their presentation: per g tissue, per whole tissue, or per cell number. In the present study, the effects of the ways of expressing the hormone sensitive lipase (HSL) activity and content were studied in rat by decreasing or increasing adipose tissue. Fasting caused a progressive decline in body weight and in the weight of the epididymal fat pad. When the HSL content was expressed per g of adipose tissue, the lipase activity and immunoreactive HSL protein content in fasting rats were higher than those in fed rats. On the other hand, when they were expressed as per fat pad, the lipase activity and immunoreactive HSL protein in fasting rats were lower than those in fed rats. The opposite results were observed in obesity. When the HSL content was expressed per g of adipose tissue, the lipase activity and immunoreactive HSL protein in obese rats were lower than in control rats. However, when the HSL content was expressed per fat pad, the lipase activity and immunoreactive HSL protein in the obese rats were higher than in the control rats. Therefore we must pay careful attention to the way of presentation of adipose tissue enzyme contents.

  19. Pathways commonly dysregulated in mouse and human obese adipose tissue: FAT/CD36 modulates differentiation and lipogenesis

    OpenAIRE

    Berger, E.; Héraud, S; Mojallal, A; Lequeux, C; Weiss-Gayet, M; Damour, O.; Géloën, A.

    2015-01-01

    Obesity is linked to adipose tissue hypertrophy (increased adipocyte cell size) and hyperplasia (increased cell number). Comparative analyses of gene datasets allowed us to identify 1426 genes which may represent common adipose phenotype in humans and mice. Among them we identified several adipocyte-specific genes dysregulated in obese adipose tissue, involved in either fatty acid storage (acyl CoA synthase ACSL1, hormone-sensitive lipase LIPE, aquaporin 7 AQP7, perilipin PLIN) or cell adhesi...

  20. Marine Fungal and Bacterial Isolates for Lipase Production: A Comparative Study.

    Science.gov (United States)

    Patnala, H S; Kabilan, U; Gopalakrishnan, L; Rao, R M D; Kumar, D S

    2016-01-01

    Lipases, belonging to the class of enzymes called hydrolases, can catalyze triglycerides to fatty acids and glycerol. They are produced by microbes of plant and animal origin, and also by marine organisms. As marine microorganisms thrive in extreme conditions, lipases isolated from their origin possess characteristics of extremozymes, retain its activity in extreme conditions and can catalyze few chemical reactions which are impossible otherwise relative to the lipase produced from terrestrial microorganisms. Lipases are useful in many industries like detergent, food, leather, pharmaceutical, diary, etc. Few commercial enzymes have been developed and the use of them in certain industries like dairy, soaps are proved to be beneficial. There are few research papers reporting the production of lipase from marine bacteria and fungi. Lipase production involves two types of fermentation processes-solid-state fermentation (SSF) and submerged fermentation (SmF). Although SmF process is used conventionally, SSF process produces lipase in higher amounts. The production is also influenced by the composition of the medium, physiochemical parameters like temperature, pH, carbon, and nitrogen sources. PMID:27452166

  1. Amplification of thermostable lipase genes fragment from thermogenic phase of domestic waste composting process

    Science.gov (United States)

    Nurhasanah, Nurbaiti, Santi; Madayanti, Fida; Akhmaloka

    2015-09-01

    Lipases are lipolytic enzymes, catalyze the hydrolysis of fatty acid ester bonds of triglycerides to produce free fatty acids and glycerol. The enzyme is widely used in various fields of biotechnological industry. Hence, lipases with unique properties (e.g.thermostable lipase) are still being explored by variation methods. One of the strategy is by using metagenomic approach to amplify the gene directly from environmental sample. This research was focused on amplification of lipase gene fragment directly from the thermogenic phase of domestic waste composting in aerated trenches. We used domestic waste compost from waste treatment at SABUGA, ITB for the sample. Total chromosomal DNA were directly extracted from several stages at thermogenic phase of compost. The DNA was then directly used as a template for amplification of thermostable lipase gene fragments using a set of internal primers namely Flip-1a and Rlip-1a that has been affixed with a GC clamp in reverse primer. The results showed that the primers amplified the gene from four stages of thermogenic phase with the size of lipase gene fragment of approximately 570 base pairs (bp). These results were further used for Denaturing Gradient Gel Electrophoresis (DGGE) analysis to determine diversity of thermostable lipase gene fragments.

  2. Crystal structure of a triacylglycerol lipase from Penicillium expansum at 1.3 A determined by sulfur SAD

    Energy Technology Data Exchange (ETDEWEB)

    Bian, Chuanbing; Yuan, Cai; Chen, Liqing; Meehan, Edward J.; Jiang, Longguang; Huang, Zixiang; Lin, Lin; Huang, Mingdong; (UAH); (Fujian); (Chinese Aca. Sci.)

    2010-04-05

    Triacylglycerol lipases (EC 3.1.1.3) are present in many different organisms including animals, plants, and microbes. Lipases catalyze the hydrolysis of long-chain triglycerides into fatty acids and glycerol at the interface between the water insoluble substrate and the aqueous phase. Lipases can also catalyze the reverse esterification reaction to form glycerides under certain conditions. Lipases of microbial origin are of considerable commercial interest for wide variety of biotechnological applications in industries, including detergent, food, cosmetic, pharmaceutical, fine chemicals, and biodiesel. Nowadays, microbial lipases have become one of the most important industrial enzymes. PEL (Penicillium expansum lipase) is a fungal lipase from Penicillium expansum strain PF898 isolated from Chinese soil that has been subjected to several generations of mutagenesis to increase its enzymatic activity. PEL belongs to the triacylglycerol lipases family, and its catalytic characteristics have been studied. The enzyme has been used in Chinese laundry detergent industry for several years (http://www.leveking.com). However, the poor thermal stability of the enzyme limits its application. To further study and improve this enzyme, PEL was cloned and sequenced. Furthermore, it was overexpressed in Pichia pastoris. PEL contains GHSLG sequence, which is the lipase consensus sequence Gly-X1-Ser-X2-Gly, but has a low amino acid sequence identities to other lipases. The most similar lipases are Rhizomucor miehei (PML) and Rhizopus niveus (PNL) with a 21% and 20% sequence identities to PEL, respectively. Interestingly, the similarity of PEL with the known esterases is somewhat higher with 24% sequence identity to feruloyl esterase A. Here, we report the 1.3 {angstrom} resolution crystal structure of PEL determined by sulfur SAD phasing. This structure not only presents a new lipase structure at high resolution, but also provides a structural platform to analyze the published

  3. Lipase biofilm deposited by Matrix Assisted Pulsed Laser Evaporation technique

    Energy Technology Data Exchange (ETDEWEB)

    Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, University of Naples “Federico II”, Napoli (Italy); Bloisi, Francesco, E-mail: bloisi@na.infn.it [SPIN – CNR, Naples (Italy); Department of Physics, University of Naples “Federico II”, Napoli (Italy); Calabria, Raffaela; Califano, Valeria [Istituto Motori – CNR, Naples (Italy); Depero, Laura E. [Department of Mechanical and Industrial Engineering, University of Brescia, Brescia (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, University of Naples “Federico II”, Napoli (Italy); Federici, Stefania [Department of Mechanical and Industrial Engineering, University of Brescia, Brescia (Italy); Massoli, Patrizio [Istituto Motori – CNR, Naples (Italy); Vicari, Luciano R.M. [SPIN – CNR, Naples (Italy); Department of Physics, University of Naples “Federico II”, Napoli (Italy)

    2015-05-01

    Highlights: • A lipase film was deposited with Matrix Assisted Pulsed Laser Evaporation technique. • FTIR spectra show that laser irradiation do not damage lipase molecule. • Laser fluence controls the characteristics of complex structure generated by MAPLE. - Abstract: Lipase is an enzyme that finds application in biodiesel production and for detection of esters and triglycerides in biosensors. Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique derived from Pulsed Laser Deposition (PLD) for deposition of undamaged biomolecules or polymers, is characterized by the use of a frozen target obtained from a solution/suspension of the guest material (to be deposited) in a volatile matrix (solvent). The presence of the solvent avoids or at least reduces the potential damage of guest molecules by laser radiation but only the guest material reaches the substrate in an essentially solvent-free deposition. MAPLE can be used for enzymes immobilization, essential for industrial application, allowing the development of continuous processes, an easier separation of products, the reuse of the catalyst and, in some cases, enhancing enzyme properties (pH, temperature stability, etc.) and catalytic activity in non-aqueous media. Here we show that MAPLE technique can be used to deposit undamaged lipase and that the complex structure (due to droplets generated during extraction from target) of the deposited material can be controlled by changing the laser beam fluence.

  4. Lipase biofilm deposited by Matrix Assisted Pulsed Laser Evaporation technique

    International Nuclear Information System (INIS)

    Highlights: • A lipase film was deposited with Matrix Assisted Pulsed Laser Evaporation technique. • FTIR spectra show that laser irradiation do not damage lipase molecule. • Laser fluence controls the characteristics of complex structure generated by MAPLE. - Abstract: Lipase is an enzyme that finds application in biodiesel production and for detection of esters and triglycerides in biosensors. Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique derived from Pulsed Laser Deposition (PLD) for deposition of undamaged biomolecules or polymers, is characterized by the use of a frozen target obtained from a solution/suspension of the guest material (to be deposited) in a volatile matrix (solvent). The presence of the solvent avoids or at least reduces the potential damage of guest molecules by laser radiation but only the guest material reaches the substrate in an essentially solvent-free deposition. MAPLE can be used for enzymes immobilization, essential for industrial application, allowing the development of continuous processes, an easier separation of products, the reuse of the catalyst and, in some cases, enhancing enzyme properties (pH, temperature stability, etc.) and catalytic activity in non-aqueous media. Here we show that MAPLE technique can be used to deposit undamaged lipase and that the complex structure (due to droplets generated during extraction from target) of the deposited material can be controlled by changing the laser beam fluence

  5. Covalent immobilization of Pseudomonas cepacia lipase on semiconducting materials

    Science.gov (United States)

    Fernandez, Renny Edwin; Bhattacharya, Enakshi; Chadha, Anju

    2008-05-01

    Lipase from Pseudomonas cepacia was covalently immobilized on crystalline silicon, porous silicon and silicon nitride surfaces. The various stages of immobilization were characterized using FTIR (Fourier transform infrared) spectroscopy. The surface topography of the enzyme immobilized surfaces was investigated using scanning electron microscopy (SEM). The quantity of the immobilized active enzyme was estimated by the para-nitrophenyl palmitate (pNPP) assay. The immobilized lipase was used for triglyceride hydrolysis and the acid produced was detected by a pH sensitive silicon nitride surface as a shift in the C- V (capacitance-voltage) characteristics of an electrolyte-insulator-semiconductor capacitor (EISCAP) thus validating the immobilization method for use as a biosensor.

  6. Covalent immobilization of Pseudomonas cepacia lipase on semiconducting materials

    International Nuclear Information System (INIS)

    Lipase from Pseudomonas cepacia was covalently immobilized on crystalline silicon, porous silicon and silicon nitride surfaces. The various stages of immobilization were characterized using FTIR (Fourier transform infrared) spectroscopy. The surface topography of the enzyme immobilized surfaces was investigated using scanning electron microscopy (SEM). The quantity of the immobilized active enzyme was estimated by the para-nitrophenyl palmitate (pNPP) assay. The immobilized lipase was used for triglyceride hydrolysis and the acid produced was detected by a pH sensitive silicon nitride surface as a shift in the C-V (capacitance-voltage) characteristics of an electrolyte-insulator-semiconductor capacitor (EISCAP) thus validating the immobilization method for use as a biosensor

  7. Covalent immobilization of Pseudomonas cepacia lipase on semiconducting materials

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Renny Edwin [Microelectronics and MEMS Laboratory, Department of Electrical Engineering, Indian Institute of Technology Madras, Chennai (India)], E-mail: rennyedwin@gmail.com; Bhattacharya, Enakshi [Microelectronics and MEMS Laboratory, Department of Electrical Engineering, Indian Institute of Technology Madras, Chennai (India)], E-mail: enakshi@ee.iitm.ac.in; Chadha, Anju [Department of Biotechnology, National Centre for Catalysis Research, Indian Institute of Technology Madras, Chennai (India)], E-mail: anjuc@iitm.ac.in

    2008-05-30

    Lipase from Pseudomonas cepacia was covalently immobilized on crystalline silicon, porous silicon and silicon nitride surfaces. The various stages of immobilization were characterized using FTIR (Fourier transform infrared) spectroscopy. The surface topography of the enzyme immobilized surfaces was investigated using scanning electron microscopy (SEM). The quantity of the immobilized active enzyme was estimated by the para-nitrophenyl palmitate (pNPP) assay. The immobilized lipase was used for triglyceride hydrolysis and the acid produced was detected by a pH sensitive silicon nitride surface as a shift in the C-V (capacitance-voltage) characteristics of an electrolyte-insulator-semiconductor capacitor (EISCAP) thus validating the immobilization method for use as a biosensor.

  8. Fatty Acid Signaling: The New Function of Intracellular Lipases

    Directory of Open Access Journals (Sweden)

    Zuzana Papackova

    2015-02-01

    Full Text Available Until recently, intracellular triacylglycerols (TAG stored in the form of cytoplasmic lipid droplets have been considered to be only passive “energy conserves”. Nevertheless, degradation of TAG gives rise to a pleiotropic spectrum of bioactive intermediates, which may function as potent co-factors of transcription factors or enzymes and contribute to the regulation of numerous cellular processes. From this point of view, the process of lipolysis not only provides energy-rich equivalents but also acquires a new regulatory function. In this review, we will concentrate on the role that fatty acids liberated from intracellular TAG stores play as signaling molecules. The first part provides an overview of the transcription factors, which are regulated by fatty acids derived from intracellular stores. The second part is devoted to the role of fatty acid signaling in different organs/tissues. The specific contribution of free fatty acids released by particular lipases, hormone-sensitive lipase, adipose triacylglycerol lipase and lysosomal lipase will also be discussed.

  9. Defective Differentiation of Adipose Precursor Cells from Lipodystrophic Mice Lacking Perilipin 1

    OpenAIRE

    Ying Lyu; Xueying Su; Jingna Deng; Shangxin Liu; Liangqiang Zou; Xiaojing Zhao; Suning Wei; Bin Geng; Guoheng Xu

    2015-01-01

    Perilipin 1 (Plin1) localizes at the surface of lipid droplets to regulate triglyceride storage and hydrolysis in adipocytes. Plin1 defect leads to low adiposity in mice and partial lipodystrophy in human. This study investigated the roles of Plin1 in adipocyte differentiation. Plin1 null (-/-) mice showed plenty of multilocular adipocytes and small unilocular adipocytes in adipose tissue, along with lack of a subpopulation of adipose progenitor cells capable of in vivo adipogenesis and along...

  10. Plant lipases: partial purification of Carica papaya lipase.

    Science.gov (United States)

    Rivera, Ivanna; Mateos-Díaz, Juan Carlos; Sandoval, Georgina

    2012-01-01

    Lipases from plants have very interesting features for application in different fields. This chapter provides an overview on some of the most important aspects of plant lipases, such as sources, applications, physiological functions, and specificities. Lipases from laticifers and particularly Carica papaya lipase (CPL) have emerged as a versatile autoimmobilized biocatalyst. However, to get a better understanding of CPL biocatalytic properties, the isolation and purification of individual C. papaya lipolytic enzymes become necessary. In this chapter, a practical protocol for partial purification of the latex-associated lipolytic activity from C. papaya is given.

  11. Familial lipoprotein lipase-activity deficiency: study of total body fatness and subcutaneous fat tissue distribution.

    Science.gov (United States)

    Brun, L D; Gagné, C; Julien, P; Tremblay, A; Moorjani, S; Bouchard, C; Lupien, P J

    1989-10-01

    Total body fatness and subcutaneous fat tissue distribution were evaluated in 19 hyperchylomicronemic patients. Eleven were males, aged 10 to 57 years, and eight were females, aged 13 to 46 years. Familial lipoprotein-lipase-activity deficiency was diagnosed by the absence of lipoprotein-lipase activity in the plasma withdrawn ten and 20 minutes after intravenous injection of ten units of heparin per kilogram of body weight. The 19 patients had skin-fold measurements for evaluation of subcutaneous fat distribution. Fifteen also underwent body density measurements by underwater weighing. Percent body fat was calculated from body density. These anthropometric data were plotted against the regression curves of 1638 normal controls of both sexes (aged 10 to 54 years) for fat tissue weight, percent body fat, subcutaneous fat/total fat mass ratio and trunk/extremity skin-fold ratio. Impairments in the process of building fat tissue reserves could not be shown in the 19 hyperchylomicronemic patients, in spite of the absence of lipoprotein-lipase activity in their postheparin plasma. It is hypothesized that normal fat tissue mass in these patients could be due partly to de novo synthesis of fatty acids by adipocytes, hydrolysis of plasma triglycerides by hepatic lipase, and/or contribution of a specific fat-tissue lipase to the catabolism of plasma triglyceride-rich lipoproteins.

  12. Colorimetric measurement of triglycerides cannot provide an accurate measure of stored fat content in Drosophila.

    Directory of Open Access Journals (Sweden)

    Bader Al-Anzi

    Full Text Available Drosophila melanogaster has recently emerged as a useful model system in which to study the genetic basis of regulation of fat storage. One of the most frequently used methods for evaluating the levels of stored fat (triglycerides in flies is a coupled colorimetric assay available as a kit from several manufacturers. This is an aqueous-based enzymatic assay that is normally used for measurement of mammalian serum triglycerides, which are present in soluble lipoprotein complexes. In this short communication, we show that coupled colorimetric assay kits cannot accurately measure stored triglycerides in Drosophila. First, they fail to give accurate readings when tested on insoluble triglyceride mixtures with compositions like that of stored fat, or on fat extracted from flies with organic solvents. This is probably due to an inability of the lipase used in the kits to efficiently cleave off the glycerol head group from fat molecules in insoluble samples. Second, the measured final products of the kits are quinoneimines, which absorb visible light in the same wavelength range as Drosophila eye pigments. Thus, when extracts from crushed flies are assayed, much of the measured signal is actually due to eye pigments. Finally, the lipoprotein lipases used in colorimetric assays also cleave non-fat glycerides. The glycerol backbones liberated from all classes of glycerides are measured through the remaining reactions in the assay. As a consequence, when these assay kits are used to evaluate tissue extracts, the observed signal actually represents the amount of free glycerols together with all types of glycerides. For these reasons, findings obtained through use of coupled colorimetric assays on Drosophila samples must be interpreted with caution. We also show here that using thin-layer chromatography to measure stored triglycerides in flies eliminates all of these problems.

  13. Sexual dimorphic regulation of body weight dynamics and adipose tissue lipolysis.

    Directory of Open Access Journals (Sweden)

    Verena Benz

    Full Text Available BACKGROUND: Successful reduction of body weight (BW is often followed by recidivism to obesity. BW-changes including BW-loss and -regain is associated with marked alterations in energy expenditure (EE and adipose tissue (AT metabolism. Since these processes are sex-specifically controlled, we investigated sexual dimorphisms in metabolic processes during BW-dynamics (gain-loss-regain. RESEARCH DESIGN: Obesity was induced in C57BL/6J male (m and female (f mice by 15 weeks high-fat diet (HFD feeding. Subsequently BW was reduced (-20% by caloric restriction (CR followed by adaptive feeding, and a regain-phase. Measurement of EE, body composition, blood/organ sampling were performed after each feeding period. Lipolysis was analyzed ex-vivo in gonadal AT. RESULTS: Male mice exhibited accelerated BW-gain compared to females (relative BW-gain m:140.5±3.2%; f:103.7±6.5%; p<0.001. In consonance, lean mass-specific EE was significantly higher in females compared to males during BW-gain. Under CR female mice reached their target-BW significantly faster than male mice (m:12.2 days; f:7.6 days; p<0.001 accompanied by a sustained sex-difference in EE. In addition, female mice predominantly downsized gonadal AT whereas the relation between gonadal and total body fat was not altered in males. Accordingly, only females exhibited an increased rate of forskolin-stimulated lipolysis in AT associated with significantly higher glycerol concentrations, lower RER-values, and increased AT expression of adipose triglyceride lipase (ATGL and hormone sensitive lipase (HSL. Analysis of AT lipolysis in estrogen receptor alpha (ERα-deficient mice revealed a reduced lipolytic rate in the absence of ERα exclusively in females. Finally, re-feeding caused BW-regain faster in males than in females. CONCLUSION: The present study shows sex-specific dynamics during BW-gain-loss-regain. Female mice responded to CR with an increase in lipolytic activity, and augmented lipid

  14. Depot-specific differences in perilipin and hormone-sensitive lipase expression in lean and obese

    Directory of Open Access Journals (Sweden)

    Beylot Michel

    2009-12-01

    Full Text Available Abstract Background Mainly dependent on hormone-sensitive lipase, lipolysis is differently impaired between fat depots in human obesity. Perilipin A expression is a critical element in adipocyte lipolysis. The present study aimed at comparing expression and subcellular distribution of perilipin and hormone-sensitive lipase in two abdominal adipose tissues of lean and obese women. We examined whether regional differences in perilipin expression contribute to impaired lipolytic rates. Methods Abdominal subcutaneous and omental adipose tissues were obtained from six lean and ten obese women. We measured total protein content and relative distribution of hormone-sensitive lipase and perilipin proteins between lipid and non-lipid fractions in tissue homogenates. Hormone-sensitive lipase and perilipin mRNA levels, adipocyte size, basal (non-stimulated and noradrenaline-stimulated lipolysis in isolated adipocytes were determined. Results Adipocytes were significantly larger in the obese versus the lean women and in subcutaneous versus omental fat. Expressed as a function of cell number, basal lipolysis and noradrenaline responsiveness were higher in subcutaneous versus omental adipocytes from the obese women (P Conclusion In both fat depots, a reduced perilipin protein expression was observed in women obesity. Perilipin protein level may contribute to differences in basal lipolysis and in adipocyte size between fat depots and may regulate lipid accumulation in adipocytes. Differences in hormone-sensitive lipase subcellular distribution were reported between fat depots in the obese women.

  15. Inhibitors of pancreatic lipase

    OpenAIRE

    Lunagariya, Nitin A.; Patel, Neeraj K.; Jagtap, Sneha C.; Bhutani, Kamlesh K.

    2014-01-01

    Obesity is a disorder of lipid metabolism and continues to be a global problem, ranking fifth for deaths worldwide. It also leads to diabetes, cardiovascular disorders, musculoskeletal disorders and some types of cancer. Obesity is regarded as the output of a long-term imbalance between energy intake and energy expenditure. Digestion and absorption of dietary lipids by pancreatic lipase, a major source of excess calorie intake, can be targeted for development of anti-obesity agents. Being the...

  16. Inactivation of lipoprotein lipase occurs on the surface of THP-1 macrophages where oligomers of angiopoietin-like protein 4 are formed

    Energy Technology Data Exchange (ETDEWEB)

    Makoveichuk, Elena; Sukonina, Valentina; Kroupa, Olessia [Department of Medical Biosciences, Physiological Chemistry Umea University, SE-901 87 Umea (Sweden); Thulin, Petra; Ehrenborg, Ewa [Atherosclerosis Research Unit, Department of Medicine, Karolinska Institutet, SE-171 76 Stockholm (Sweden); Olivecrona, Thomas [Department of Medical Biosciences, Physiological Chemistry Umea University, SE-901 87 Umea (Sweden); Olivecrona, Gunilla, E-mail: Gunilla.Olivecrona@medbio.umu.se [Department of Medical Biosciences, Physiological Chemistry Umea University, SE-901 87 Umea (Sweden)

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Lipoprotein lipase (LPL) activity is controlled by ANGPTL4 in THP-1 macrophages. Black-Right-Pointing-Pointer Both LPL and ANGPTL4 bind to THP-1 macrophages in a heparin-releasable fashion. Black-Right-Pointing-Pointer Only monomers of ANGPTL4 are present within THP-1 macrophages. Black-Right-Pointing-Pointer Covalent oligomers of ANGPTL4 appear on cell surface and in medium. Black-Right-Pointing-Pointer Inactivation of LPL coincide with ANGPTL4 oligomer formation on cell surfaces. -- Abstract: Lipoprotein lipase (LPL) hydrolyzes triglycerides in plasma lipoproteins causing release of fatty acids for metabolic purposes in muscles and adipose tissue. LPL in macrophages in the artery wall may, however, promote foam cell formation and atherosclerosis. Angiopoietin-like protein (ANGPTL) 4 inactivates LPL and ANGPTL4 expression is controlled by peroxisome proliferator-activated receptors (PPAR). The mechanisms for inactivation of LPL by ANGPTL4 was studied in THP-1 macrophages where active LPL is associated with cell surfaces in a heparin-releasable form, while LPL in the culture medium is mostly inactive. The PPAR{delta} agonist GW501516 had no effect on LPL mRNA, but increased ANGPTL4 mRNA and caused a marked reduction of the heparin-releasable LPL activity concomitantly with accumulation of inactive, monomeric LPL in the medium. Intracellular ANGPTL4 was monomeric, while dimers and tetramers of ANGPTL4 were present in the heparin-releasable fraction and medium. GW501516 caused an increase in the amount of ANGPTL4 oligomers on the cell surface that paralleled the decrease in LPL activity. Actinomycin D blocked the effects of GW501516 on ANGPTL4 oligomer formation and prevented the inactivation of LPL. Antibodies against ANGPTL4 interfered with the inactivation of LPL. We conclude that inactivation of LPL in THP-1 macrophages primarily occurs on the cell surface where oligomers of ANGPTL4 are formed.

  17. Inactivation of lipoprotein lipase occurs on the surface of THP-1 macrophages where oligomers of angiopoietin-like protein 4 are formed

    International Nuclear Information System (INIS)

    Highlights: ► Lipoprotein lipase (LPL) activity is controlled by ANGPTL4 in THP-1 macrophages. ► Both LPL and ANGPTL4 bind to THP-1 macrophages in a heparin-releasable fashion. ► Only monomers of ANGPTL4 are present within THP-1 macrophages. ► Covalent oligomers of ANGPTL4 appear on cell surface and in medium. ► Inactivation of LPL coincide with ANGPTL4 oligomer formation on cell surfaces. -- Abstract: Lipoprotein lipase (LPL) hydrolyzes triglycerides in plasma lipoproteins causing release of fatty acids for metabolic purposes in muscles and adipose tissue. LPL in macrophages in the artery wall may, however, promote foam cell formation and atherosclerosis. Angiopoietin-like protein (ANGPTL) 4 inactivates LPL and ANGPTL4 expression is controlled by peroxisome proliferator-activated receptors (PPAR). The mechanisms for inactivation of LPL by ANGPTL4 was studied in THP-1 macrophages where active LPL is associated with cell surfaces in a heparin-releasable form, while LPL in the culture medium is mostly inactive. The PPARδ agonist GW501516 had no effect on LPL mRNA, but increased ANGPTL4 mRNA and caused a marked reduction of the heparin-releasable LPL activity concomitantly with accumulation of inactive, monomeric LPL in the medium. Intracellular ANGPTL4 was monomeric, while dimers and tetramers of ANGPTL4 were present in the heparin-releasable fraction and medium. GW501516 caused an increase in the amount of ANGPTL4 oligomers on the cell surface that paralleled the decrease in LPL activity. Actinomycin D blocked the effects of GW501516 on ANGPTL4 oligomer formation and prevented the inactivation of LPL. Antibodies against ANGPTL4 interfered with the inactivation of LPL. We conclude that inactivation of LPL in THP-1 macrophages primarily occurs on the cell surface where oligomers of ANGPTL4 are formed.

  18. Rigorous kinetic model considering positional specificity of lipase for enzymatic stepwise hydrolysis of triolein in biphasic oil-water system.

    Science.gov (United States)

    Hermansyah, Heri; Wijanarko, Anondho; Kubo, Masaki; Shibasaki-Kitakawa, Naomi; Yonemoto, Toshikuni

    2010-09-01

    A rigorous kinetic model describing the stepwise triglyceride hydrolysis at the oil-water interface, based on the Ping Pong Bi Bi mechanism using suspended lipase having positional specificity, was constructed. The preference of the enzyme to cleave to the ester bonds at the edge and the center of the glycerol backbone of the substrates (tri-, di- or monoglyceride) was incorporated in the model. This model was applied to the experimental results for triolein hydrolysis using suspended Porcine pancreatic lipase (an sn-1,3 specific lipase) and Candida rugosa lipase (a non-specific lipase) in a biphasic oil-water system under various operating conditions. In order to discuss the model's advantages, other models that do not consider the positional specificity of the lipase were also applied to our experimental results. The model considering the positional specificity of the lipase gave results which fit better with the experimental data and described the effect of the initial enzyme concentration, the interfacial area, and the initial concentrations of triolein on the entire process of the stepwise triolein hydrolysis. This model also gives a good representation of the rate for cleaving the respective ester bonds of each substrate by each type of lipase.

  19. Catalytically inactive lipoprotein lipase expression in muscle of transgenic mice increases very low density lipoprotein uptake: Direct evidence that lipoprotein lipase bridging occurs in vivo

    OpenAIRE

    Merkel, Martin; Kako, Yuko; Radner, Herbert; Cho, Irene S.; Ramasamy, Ravi; Brunzell, John D.; Goldberg, Ira J.; Breslow, Jan L.

    1998-01-01

    Lipoprotein lipase (LPL) is the central enzyme in plasma triglyceride hydrolysis. In vitro studies have shown that LPL also can enhance lipoprotein uptake into cells via pathways that are independent of catalytic activity but require LPL as a molecular bridge between lipoproteins and proteoglycans or receptors. To investigate whether this bridging function occurs in vivo, two transgenic mouse lines were established expressing a muscle creatine kinase promoter-driven human LPL (hLPL) minigene ...

  20. The fatty liver dystrophy (fld) mutation: Developmentally related alterations in hepatic triglyceride metabolism and protein expression

    Energy Technology Data Exchange (ETDEWEB)

    Reue, K.; Rehnmark, S.; Cohen, R.D.; Leete, T.H.; Doolittle, M.H. [West Los Angeles VA Medical Center, CA (United States). Lipid Research Lab.]|[Univ. of California, Los Angeles, CA (United States). Dept. of Medicine; Giometti, C.S.; Mishler, K. [Argonne National Lab., IL (United States); Slavin, B.G. [Univ. of Southern California, Los Angeles, CA (United States)

    1997-07-01

    Fatty liver dystrophy (fld) is an autosomal recessive mutation in mice characterized by hypertriglyceridemia and development of a fatty liver in the early neonatal period. Also associated with the fld phenotype is a tissue-specific deficiency in the expression of lipoprotein lipase and hepatic lipase, as well as elevations in hepatic apolipoprotein A-IV and apolipoprotein C-II mRNA levels. Although these lipid abnormalities resolve at the age of weaning, adult mutant mice exhibit a peripheral neuropathy associated with abnormal myelin formation. The fatty liver in fld/fld neonates is characterized by the accumulation of large triglyceride droplets within the parenchymal cells, and these droplets persist within isolated hepatocytes maintained in culture for several days. To identify the metabolic defect that leads to lipid accumulation, the authors investigated several aspects of cellular triglyceride metabolism. The mutant mice exhibited normal activity of acid triacylglycerol lipase, an enzyme thought to be responsible for hydrolysis of dietary triglycerides in the liver. Metabolic labeling studies performed with oleic acid revealed that free fatty acids accumulate in the liver of 3 day old fld/fld mice, but not in adults. This accumulation in liver was mirrored by elevated free fatty acid levels in plasma of fld/fld neonates, with levels highest in very young mice and returning to normal by the age of one month. Quantitation of fatty acid oxidation in cells isolated from fld/fld neonates revealed that oxidation rate is reduced 60% in hepatocytes and 40% in fibroblasts; hepatocytes from adult fld/fld mice exhibited an oxidation rate similar to those from wild-type mice.

  1. High-Level Expression of Pro-Form Lipase from Rhizopus oryzae in Pichia pastoris and Its Purification and Characterization

    Directory of Open Access Journals (Sweden)

    Jian-Rong Wang

    2013-12-01

    Full Text Available A gene encoding Rhizopus oryzae lipase containing prosequence (ProROL was cloned into the pPICZαA and electrotransformed into the Pichia pastoris X-33 strain. The lipase was functionally expressed and secreted in Pichia pastoris with a molecular weight of 35 kDa. The maximum lipase activity of recombinant lipase (rProROL was 21,000 U/mL, which was obtained in a fed-batch cultivation after 168 h induction with methanol in a 50-L bioreactor. After fermentation, the supernatant was concentrated by ultrafiltration with a 10 kDa cut off membrane and purified with ion exchange chromatography using SP Sepharose Fast Flow chromatography. The optimum pH and temperature of the rProROL were pH 9.0 and 40 °C, respectively. The lipase was stable from pH 4.0 to 9.0 and from 25 to 55 °C. The enzyme activity was enhanced by Ca2+ and inhibited by Hg2+ and Ag+. The lipase showed high activity toward triglyceride-Tripalmitin (C16:0 and triglyceride-Trilaurin (C12:0.

  2. Variation in the ovine hormone-sensitive lipase gene (HSL) and its association with growth and carcass traits in New Zealand Suffolk sheep.

    Science.gov (United States)

    Yang, Guo; Forrest, Rachel; Zhou, Huitong; Hickford, Jonathan

    2014-01-01

    The hormone-sensitive lipase (HSL) plays an important role in the regulation of lipolysis in adipose tissues, by catalysing a rate-limiting step in triglyceride hydrolysis. Variation within the human HSL gene (HSL) has been associated with an increased risk of obesity. In this study, variation within three regions (exon 3-4, exon 5-6 and exon 9) of ovine HSL was investigated in 538 Suffolk lambs bred from 13 independent sires using PCR-SSCP. Four sequence variants of intron 5 (designated A-D) and two variants of exon 9 (designated a and b) of ovine HSL were detected. No variation was found in exon 3-4 of the gene. The associations of the variation within ovine HSL with post-weaning growth and carcass traits including eye muscle depth (EMD), eye muscle width (EMW) and fat depth above the eye muscle (FDM) were assessed in 262 of the above 538 lambs using general linear mixed-effects models. In the single variant models, the presence of intron 5 A in a lamb's genotype was associated with reduced EMD (P = 0.036) and EMW (P = 0.018), whereas the presence of intron 5 C was associated with increased EMD (P HSL intron 5 variants and post-weaning growth, or between HSL exon 9 variants, post-weaning growth or carcass traits, were found.

  3. X-ray structure of Candida antarctica lipase A shows a novel lid structure and a likely mode of interfacial activation

    OpenAIRE

    Ericsson, Daniel J.; Kasrayan, Alex; Johansson, Patrik; Bergfors, Terese; Sandström, Anders G.; Bäckvall, Jan-Erling; Mowbray, Sherry L.

    2008-01-01

    In nature, lipases (EC 3.1.1.3) catalyze the hydrolysis of triglycerides to form glycerol and fatty acids. Under the appropriate conditions, the reaction is reversible, and so biotechnological applications commonly make use of their capacity for esterification as well as for hydrolysis of a wide variety of compounds. In the present paper, we report the X-ray structure of lipase A from Candida antarctica, solved by single isomorphous replacement with anomalous scattering, and refined to 2.2-A ...

  4. Aspects of plasma triglyceride metabolism in children

    NARCIS (Netherlands)

    P.P. Forget

    1975-01-01

    textabstractThis thesis aimed at investigating some aspects of plasma triglyceride metabolism in children. In the introduction general aspects of plasma triglyceride metabolism are presented. Chapter 1 reviews recent litterature data on the intravenous fat tolerance test and on plasma postheparin li

  5. Serum triglycerides and risk of cardiovascular disease.

    NARCIS (Netherlands)

    Boullart, I.; Graaf, J. de; Stalenhoef, A.F.H.

    2012-01-01

    Dyslipidemia, especially elevated serum levels of cholesterol, is causally related to cardiovascular disease. The specific role of triglycerides has long been controversial. In this article we discuss the role of serum triglycerides in relation to the risk of cardiovascular disease. First, the (path

  6. Penicillium restrictum lipases : A comparative study and characterization of enzymes with different degrees of purity

    Directory of Open Access Journals (Sweden)

    JESUS M.F.C.P.

    1999-01-01

    Full Text Available Penicillium restrictum was identified as a promising strain for lipase production due to enzyme production yield and thermal stability of the enzyme. This work presents results of lipase purification and enzyme stability versus pH. Ultrafiltration and precipitation with ammonium sulphate were used as initial purification steps. The partially purified enzyme preparation showed an increase in stability as pH increased. The crude enzymatic preparation was assayed with different oils and tributirin and showed a major catalytic activity for triglycerides of medium/long-chain fatty acids. Further purification steps were conducted on an analytical scale. The initial attempt to use gel filtration was abandoned as lipase lost its stability after this chromatographic procedure. The fast ion-exchange chromatography was performed on a Mono Q column, and two peaks with lipolytic activity were isolated and analysed by electrophoresis.

  7. Chylous ascites secondary to hyperlipidemic pancreatitis with normal serum amylase and lipase

    OpenAIRE

    Khan, Fahmi Yousef; Matar, Issa

    2007-01-01

    A 54-year old man with a family history of hyperlipidemia was admitted with a 12 h history of severe generalized abdominal pain associated with nausea, vomiting and abdominal distension. Examination of the abdomen revealed tenderness in the periumblical area with shifting dullness. Serum pancreatic amylase was 29 IU/L and lipase 44 IU/L, triglyceride 36.28 mmol/L. Ultrasound showed ascites. CT of the abdomen with contrast showed inflammatory changes surrounding the pancreas consistent with ac...

  8. Pancreatic carboxyl ester lipase: a circulating enzyme that modifies normal and oxidized lipoproteins in vitro.

    OpenAIRE

    Shamir, R; Johnson, W. J.; Morlock-Fitzpatrick, K; Zolfaghari, R; Li, L; mas, e; Lombardo, D.; Morel, D W; Fisher, E A

    1996-01-01

    Pancreatic carboxyl ester lipase (CEL) hydrolyzes cholesteryl esters (CE), triglycerides (TG), and lysophospholipids, with CE and TG hydrolysis stimulated by cholate. Originally thought to be confined to the gastrointestinal system, CEL has been reported in the plasma of humans and other mammals, implying its potential in vivo to modify lipids associated with LDL, HDL (CE, TG), and oxidized LDL (lysophosphatidylcholine, lysoPC). We measured the concentration of CEL in human plasma as 1.2+/-0....

  9. The lipoprotein lipase gene in combined hyperlipidemia: evidence of a protective allele depletion

    OpenAIRE

    Malloy Mary J; Pullinger Clive R; Kulkarni Medha V; Wung Shu-Fen; Kane John P; Aouizerat Bradley E

    2006-01-01

    Abstract Background Lipoprotein Lipase (LPL), a key enzyme in lipid metabolism, catalyzes the hydrolysis of triglycerides (TG) from TG-rich lipoproteins, and serves a bridging function that enhances the cellular uptake of lipoproteins. Abnormalities in LPL function are associated with pathophysiological conditions, including familial combined hyperlipidemia (FCH). Whereas two LPL susceptibility alleles were found to co-segregate in a few FCH kindred, a role for common, protective alleles rema...

  10. The common biological basis for common complex diseases: evidence from lipoprotein lipase gene

    OpenAIRE

    Xie, Cui; Wang, Zeng Chan; Liu, Xiao Feng; Yang, Mao Sheng

    2009-01-01

    The lipoprotein lipase (LPL) gene encodes a rate-limiting enzyme protein that has a key role in the hydrolysis of triglycerides. Hypertriglyceridemia, one widely prevalent syndrome of LPL deficiency and dysfunction, may be a risk factor in the development of dyslipidemia, type II diabetes (T2D), essential hypertension (EH), coronary heart disease (CHD) and Alzheimer's disease (AD). Findings from earlier studies indicate that LPL may have a role in the pathology of these diseases and therefore...

  11. Lipoprotein lipase increases low density lipoprotein retention by subendothelial cell matrix.

    OpenAIRE

    Saxena, U; Klein, M. G.; Vanni, T M; Goldberg, I J

    1992-01-01

    Lipoprotein lipase (LPL), the rate-limiting enzyme for hydrolysis of plasma lipoprotein triglycerides, is a normal constituent of the arterial wall. We explored whether LPL affects (a) lipoprotein transport across bovine aortic endothelial cells or (b) lipoprotein binding to subendothelial cell matrix (retention). When bovine milk LPL was added to endothelial cell monolayers before addition of 125I-labeled LDL, LDL transport across the monolayers was unchanged; but, at all concentrations of L...

  12. Lipase Maturation Factor 1: a lipase chaperone involved in lipid metabolism

    OpenAIRE

    Péterfy, Miklós

    2011-01-01

    Mutations in lipase maturation factor 1 (LMF1) are associated with severe hypertriglyceridemia in mice and human subjects. The underlying cause is impaired lipid clearance due to lipase deficiency. LMF1 is a chaperone of the endoplasmic reticulum (ER) and it is critically required for the post-translational activation of three vascular lipases: lipoprotein lipase (LPL), hepatic lipase (HL) and endothelial lipase (EL). As LMF1 is only required for the maturation of homodimeric, but not monomer...

  13. Orientating lipase molecules through surface chemical control for enhanced activity: A QCM-D and ToF-SIMS investigation.

    Science.gov (United States)

    Joyce, Paul; Kempson, Ivan; Prestidge, Clive A

    2016-06-01

    Bio-active materials consisting of lipase encapsulated within porous silica particles were engineered to control the adsorption kinetics and molecular orientation of lipase, which play critical roles in the digestion kinetics of triglycerides. The adsorption kinetics of Candida antartica lipase A (CalA) was monitored using quartz crystal microbalance with dissipation (QCM-D) and controlled by altering the hydrophobicity of a silica binding support. The extent of adsorption was 2-fold greater when CalA was adsorbed onto hydrophobic silica compared to hydrophilic silica. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) fragmentation patterns, in conjunction with multivariate statistics, demonstrated enhanced exposure of the lipase's catalytic domain, specifically the histidine group responsible for activity, when CalA was adsorbed on hydrophilic silica. Consequently, lipid digestion kinetics were enhanced when CalA was loaded in hydrophilic porous silica particles, i.e., a 2-fold increase in the pseudo-first-order rate constant for digestion when compared to free lipase. In contrast, digestion kinetics were inhibited when CalA was hosted in hydrophobic porous silica, i.e., a 5-fold decrease in pseudo-first-order rate constant for digestion when compared to free lipase. These findings provide valuable insights into the mechanism of lipase action which can be exploited to develop smarter food and drug delivery systems consisting of porous lipid-based materials.

  14. Regulation and role of hormone-sensitive lipase in rat skeletal muscle

    DEFF Research Database (Denmark)

    Donsmark, Morten; Langfort, Jozef; Holm, Cecilia;

    2004-01-01

    -sensitive lipase (HSL). This enzyme is known to be rate limiting for intracellular TG hydrolysis in adipose tissue. The presence of HSL has been demonstrated in all muscle fibre types by Western blotting of muscle fibres isolated by collagenase treatment or after freeze-drying. The content of HSL varies between...... fibre types, being higher in oxidative fibres than in glycolytic fibres. When analysed under conditions optimal for HSL, neutral lipase activity in muscle can be stimulated by adrenaline as well as by contractions. These increases are abolished by the presence of anti-HSL antibody during analysis....... Moreover, immunoprecipitation with affinity-purified anti-HSL antibody causes similar reductions in muscle HSL protein concentration and in measured neutral lipase responses to contractions. The immunoreactive HSL in muscle is stimulated by adrenaline via beta-adrenergic activation of c...

  15. Abnormal Patterns of Lipoprotein Lipase Release into the Plasma in GPIHBP1-deficient Mice*

    OpenAIRE

    Weinstein, Michael M.; Yin, Liya; Beigneux, Anne P.; Davies, Brandon S. J.; Gin, Peter; Estrada, Kristine; Melford, Kristan; Bishop, Joseph R.; Esko, Jeffrey D.; Dallinga-Thie, Geesje M.; Fong, Loren G.; Bensadoun, André; Young, Stephen G.

    2008-01-01

    GPIHBP1-deficient mice (Gpihbp1–/–) exhibit severe chylomicronemia. GPIHBP1 is located within capillaries of muscle and adipose tissue, and expression of GPIHBP1 in Chinese hamster ovary cells confers upon those cells the ability to bind lipoprotein lipase (LPL). However, there has been absolutely no evidence that GPIHBP1 actually interacts with LPL in vivo. Heparin is known to release LPL from its in vivo binding sites, allowing it to enter the plasma. After an injection ...

  16. Adipose tissue fibrosis

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    The increasing prevalence of obesity causes a majorinterest in white adipose tissue biology. Adipose tissuecells are surrounded by extracellular matrix proteinswhose composition and remodeling is of crucial importancefor cell function. The expansion of adipose tissue inobesity is linked to an inappropriate supply with oxygenand hypoxia development. Subsequent activation ofhypoxia inducible factor 1 (HIF-1) inhibits preadipocytedifferentiation and initiates adipose tissue fibrosis. Therebyadipose tissue growth is limited and excess triglyceridesare stored in ectopic tissues. Stressed adipocytes andhypoxia contribute to immune cell immigration andactivation which further aggravates adipose tissuefibrosis. There is substantial evidence that adipose tissuefibrosis is linked to metabolic dysfunction,both in rodentmodels and in the clinical setting. Peroxisome proliferatoractivated receptor gamma agonists and adiponectin bothreduce adipose tissue fibrosis, inflammation and insulinresistance. Current knowledge suggests that antifibroticdrugs, increasing adipose tissue oxygen supply or HIF-1antagonists will improve adipose tissue function andthereby ameliorate metabolic diseases.

  17. Biodiesel production with immobilized lipase: A review.

    Science.gov (United States)

    Tan, Tianwei; Lu, Jike; Nie, Kaili; Deng, Li; Wang, Fang

    2010-01-01

    Fatty acid alkyl esters, also called biodiesel, are environmentally friendly and show great potential as an alternative liquid fuel. Biodiesel is produced by transesterification of oils or fats with chemical catalysts or lipase. Immobilized lipase as the biocatalyst draws high attention because that process is "greener". This article reviews the current status of biodiesel production with immobilized lipase, including various lipases, immobilization methods, various feedstocks, lipase inactivation caused by short chain alcohols and large scale industrialization. Adsorption is still the most widely employed method for lipase immobilization. There are two kinds of lipase used most frequently especially for large scale industrialization. One is Candida antartica lipase immobilized on acrylic resin, and the other is Candida sp. 99-125 lipase immobilized on inexpensive textile membranes. However, to further reduce the cost of biodiesel production, new immobilization techniques with higher activity and stability still need to be explored.

  18. Physical inactivity amplifies the sensitivity of skeletal muscle to the lipid-induced downregulation of lipoprotein lipase activity.

    Science.gov (United States)

    Zderic, Theodore W; Hamilton, Marc T

    2006-01-01

    Physical inactivity is a risk factor for lipoprotein disorders and the metabolic syndrome. Physical inactivity has a powerful effect on suppressing lipoprotein lipase (LPL) activity in skeletal muscle, the rate-limiting enzyme for hydrolysis of triglyceride (TG)-rich lipoproteins. We tested the ability of several compounds to prevent the decrease in LPL. The present study minimized standing and ordinary light nonexercise movements in rats to compare the effects of inactivity and nonexercise activity thermogenesis (NEAT) on LPL activity. The key new insight was that the typically quick decrease in LPL activity of oxidative muscle caused by physical inactivity was prevented by nicotinic acid (NA), whereas inhibitors of TNF-alpha, inducible nitric oxide synthase, and NF-kappaB had no such effect. NA was administered at a dose known to acutely impede the appearance of plasma TG from the liver and free fatty acids from adipose tissue, and it was effective at intentionally lowering plasma lipid concentrations to the same level in active and inactive groups. As measured from heparin-releasable LPL activity, LPL in the microvasculature of the most oxidative muscles was approximately 90% lower in the inactive group compared with controls, and this suppression was completely blocked by NA. In contrast to inactivity, NA did not raise muscle LPL in ambulatory controls, whereas a large exogenous fat delivery did decrease LPL activity. In vitro control studies revealed that NA did not have a direct effect on skeletal muscle LPL activity. In conclusion, physical inactivity amplifies the ability of plasma lipids to suppress muscle LPL activity. The light ambulatory contractions responsible for NEAT are sufficient for mitigating these deleterious effects. PMID:16195388

  19. Lipase - Catalyzed glycerolysis of sunflower oil to produce partial glycerides.

    OpenAIRE

    Zaher, F. A.; Aly, Saadia M.; El-Kinawy, O. S.

    1998-01-01

    Partial glycerides were prepared by glycerolysis of sunflower oil in presence of lipase enzyme as catalyst. Six lipases of different origins were used and compared for their catalytic activity. These include Chromobacterium lipase, pancreatic lipase, Rhizopus arrhizus lipase, lyophilized lipase (plant lipase) in addition to two lipase preparations derived from Rhizopus japonicas; Lilipase A-10 and Lilipase B-2. Chromobacterium&...

  20. Purification and biochemical characterization of a halotolerant Staphylococcus sp. extracellular lipase.

    Science.gov (United States)

    Daoud, Lobna; Kamoun, Jannet; Ali, Madiha Bou; Jallouli, Raida; Bradai, Rim; Mechichi, Tahar; Gargouri, Youssef; Ali, Yassine Ben; Aloulou, Ahmed

    2013-06-01

    We have isolated a lipolytic halotolerant bacterium, designated as CJ3, that was identified as a Staphylococcus sp. Culture conditions were optimized and the highest extracellular lipase production amounting to 5 U/ml was achieved after 24 h of cultivation. The extracellular lipase was purified 24-fold by ammonium sulfate precipitation and a Sephacryl S-200 chromatography, and its molecular mass was found to be around 38 kDa, as revealed by SDS-PAGE and gel filtration. The lipase substrate specificity was investigated using short (tributyrin) and long (olive oil) chain triglyceride substrates. The lipase was inhibited by submicellar concentrations of Triton X-100, and maximum specific activities were found to be 802 U/mg on tributyrin and 260 U/mg on olive oil at pH 8.0 and 45 °C. The lipase was fairly stable in the pH range from 6.0 to 9.0, and about 69% of its activity was retained after incubation at 45 °C for 60 min. The enzyme showed a high tolerance to a wide range of salt concentration and a good stability in organic solvents, especially in long-chain alcohols.

  1. Comparison of serum triglyceride levels with propofol in long chain triglyceride and propofol in medium and long chain triglyceride after short term anesthesia in pediatric patients

    OpenAIRE

    Ishwar Bhukal; Gokul Thimmarayan; Indu Bala; Sohan Lal Solanki; Tanvir Samra

    2014-01-01

    Background: Significant increase in serum triglyceride (ST) concentration have been described in adult population after prolonged administration of propofol formulation containing long chain triglyceride (LCT). Though, medium chain triglyceride-LCT (MCT-LCT) propofol when compared with LCT propofol for long-term sedation in adults resulted in identical triglyceride levels, the elimination of triglyceride was faster in patients administered MCT-LCT propofol. Materials and Methods: A total of 4...

  2. EST Table: NM_001172458 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available 08152(metabolic process) 10/09/29 100 %/341 aa ref|NP_001165929.1| adipose triglyceride lipase brummer [Bomb...yx mori] gb|ADC34595.1| adipose triglyceride lipase brummer [Bombyx mori] 10/09/13 69 %/341 aa FBpp0265011|D

  3. MOLECULAR MODELING AND DOCKING STUDIES OF COLD ACTIVE LIPASE FROM Pseudomonas fluorescens

    Directory of Open Access Journals (Sweden)

    G. N. Gupta

    2015-03-01

    Full Text Available Molecular Modeling is essential tool in the drug design process describes the generation, manipulation or representation of 3D structures of the molecules and associated physico-chemical properties while docking predicts the preferred orientation of one molecule to a second when bound to each other to form a stable complex. A cold active lipase producing potential psychrophilic bacteria (GN was isolated and identified by 16S rRNA molecular studies as Pseudomonas vancouverensis. Lipase gene from closely related species P. fluorescens was investigated for their functional role and in silico characterization using molecular modeling and docking studies. A 3D structure of lipase gene was generated with SWISS-MODEL and Discovery Studio 3.0. The stereochemistry of the constructed model of cold active lipase was subjected to energy minimization and the stereo-chemical quality of the predicted structure was assessed. The superimposition of the template (PDBID: 2Z8X with predicted structure showed that weighted root mean square deviation of Cα trace between the template and the final refined model was 0.2 Å with a significant Zscore of 8.2 and sequence identity was 80.5%. Three ligands P-Nitrophenol, Acetate ion and Diethyl phosphonate were taken for docking calculation with generated structure. They were interacting on the functional motifs of predicted model. It has been observed that Leu26, Tyr29, Asn31, Asp33, Pro315 and Thr316 residues were involved in hydrogen bonding interactions with selected ligands. So these interacted residues can be used as prominent active binding sites and which was common to the predicted active site. Based on above investigations it has been found that P. vancouverensis lipase protein can play a similar role in lipid metabolic process and triglyceride lipase functional activity as reported for P. fluorescens lipase protein.

  4. [The Integration and Regulation of Hormone-Sensitive Lipase in Reproductive System].

    Science.gov (United States)

    Wang, Wei-yi; Xu, Guo-Heng

    2015-02-01

    Hormone-sensitive lipase (HSL) has long been considered as a classical rate-limiting enzyme during lipolysis since it was first described in 1960s. HSL is regulated mainly by catecholamine, including adrenalin. Studies in recent years indicated that the substrates for HSL are not only triglycerides, but also diacylglycerol with the catalytic activity is ten times that of triglycerides, glycerol esters and cholesterol esters, which overthrow the opinion that HSL is specific to triglyceride. The scientists have generated HSL gene knockout mice and confirmed HSL is widely located in the reproductive system, which indicates that HSL may play an important role in the regulation of physiological and pathophysiological process in the reproductive system. Here, we will focus on the features of the HSL gene, mRNA and its protein, and summarize the HSL functions in the reproductive system.

  5. S447X variant of the lipoprotein lipase gene, lipids, and risk of coronary heart disease in 3 prospective cohort studies

    DEFF Research Database (Denmark)

    Jensen, M.K.; Rimm, E.B.; Rader, D.;

    2009-01-01

    Background Lipoprotein lipase (LPL) has a prominent role in the metabolism of triglycerides (TGs) and high-density lipoprotein cholesterol (HDL-C) and is a potential interesting target for the development of antiatherogenic treatment. To provide deeper insight into the role of natural variation i...

  6. Production of Truncated Candida antarctica Lipase B Gene Using Automated PCR Gene Assembly Protocol and Expression in Yeast for use in Ethanol and Biodiesel Production.

    Science.gov (United States)

    An improved column-based process for production of biodiesel was developed using a column containing a strongly basic anion-exchange resin in sequence with a column containing a resin to which a lipase biocatalyst is bound. Currently most biodiesel is produced by transesterification of triglyceride...

  7. Dynamics of human adipose lipid turnover in health and metabolic disease

    OpenAIRE

    Arner, Peter; Bernard, Samuel; Salehpour, Mehran; Possnert, Göran; Liebl, Jakob; Steier, Peter; Buchholz, Bruce A.; Eriksson, Mats; Arner, Erik; Hauner, Hans; Skurk, Thomas; Rydén, Mikael; Frayn, Keith N.; Spalding, Kirsty L.

    2011-01-01

    Adipose tissue mass is determined by the storage and removal of triglycerides in adipocytes. Little is known, however, about adipose lipid turnover in humans in health and pathology. To study this in vivo, lipid age was determined by measuring nuclear bomb test-derived 14C in adipocyte lipids. We report that during the average ten year life span of human adipocytes, triglycerides are renewed six times. Lipid age is independent of adipocyte size, is very stable across a wide range of adult age...

  8. Biodegradable products by lipase biocatalysis.

    Science.gov (United States)

    Linko, Y Y; Lämsä, M; Wu, X; Uosukainen, E; Seppälä, J; Linko, P

    1998-11-18

    The interest in the applications of biocatalysis in organic syntheses has rapidly increased. In this context, lipases have recently become one of the most studied groups of enzymes. We have demonstrated that lipases can be used as biocatalyst in the production of useful biodegradable compounds. A number of examples are given. 1-Butyl oleate was produced by direct esterification of butanol and oleic acid to decrease the viscosity of biodiesel in winter use. Enzymic alcoholysis of vegetable oils without additional organic solvent has been little investigated. We have shown that a mixture of 2-ethyl-1-hexyl esters can be obtained in a good yield by enzymic transesterification from rapeseed oil fatty acids for use as a solvent. Trimethylolpropane esters were also similarly synthesized as lubricants. Finally, the discovery that lipases can also catalyze ester syntheses and transesterification reactions in organic solvent systems has opened up the possibility of enzyme catalyzed production of biodegradable polyesters. In direct polyesterification of 1,4-butanediol and sebacic acid, polyesters with a mass average molar mass of the order of 56,000 g mol-1 or higher, and a maximum molar mass of about 130,000 g mol-1 were also obtained by using lipase as biocatalyst. Finally, we have demonstrated that also aromatic polyesters can be synthesized by lipase biocatalysis, a higher than 50,000 g mol-1 mass average molar mass of poly(1,6-hexanediyl isophthalate) as an example. PMID:9866859

  9. Lipases and Its Application in Food Industry

    Institute of Scientific and Technical Information of China (English)

    WANG Ting; QIN Gang

    2010-01-01

    Lipases(triacylglycerol acylhydrolases,EC 3.1.1.3)occur widely in nature.It catalyze the hydrolysis and the synthesis of esters formed from glycerol and long-chain fatty acids.Lipases are commercially significant,this article discusses the source,structure,character and preparative method,the applications of lipases in food industry are discussed too.

  10. A sequence variation (I148M) in PNPLA3 associated with nonalcoholic fatty liver disease disrupts triglyceride hydrolysis.

    Science.gov (United States)

    He, Shaoqing; McPhaul, Christopher; Li, John Zhong; Garuti, Rita; Kinch, Lisa; Grishin, Nick V; Cohen, Jonathan C; Hobbs, Helen H

    2010-02-26

    Obesity and insulin resistance are associated with deposition of triglycerides in tissues other than adipose tissue. Previously, we showed that a missense mutation (I148M) in PNPLA3 (patatin-like phospholipase domain-containing 3 protein) is associated with increased hepatic triglyceride content in humans. Here we examined the effect of the I148M substitution on the enzymatic activity and cellular location of PNPLA3. Structural modeling predicted that the substitution of methionine for isoleucine at residue 148 would restrict access of substrate to the catalytic serine at residue 47. In vitro assays using recombinant PNPLA3 partially purified from Sf9 cells confirmed that the wild type enzyme hydrolyzes emulsified triglyceride and that the I148M substitution abolishes this activity. Expression of PNPLA3-I148M, but not wild type PNPLA3, in cultured hepatocytes or in the livers of mice increased cellular triglyceride content. Cell fractionation studies revealed that approximately 90% of wild type PNPLA3 partitioned between membranes and lipid droplets; substitution of isoleucine for methionine at position 148 did not alter the subcellular distribution of the protein. These data are consistent with PNPLA3-I148M promoting triglyceride accumulation by limiting triglyceride hydrolysis.

  11. Short-term oleoyl-estrone treatment affects capacity to manage lipids in rat adipose tissue

    Directory of Open Access Journals (Sweden)

    Remesar Xavier

    2007-08-01

    Full Text Available Abstract Background Short-term OE (oleoyl-estrone treatment causes significant decreases in rat weight mainly due to adipose tissue loss. The aim of this work was to determine if OE treatment affects the expression of genes that regulate lipid metabolism in white adipose tissue. Results Gene expression in adipose tissue from female treated rats (48 hours was analysed by hybridization to cDNA arrays and levels of specific mRNAs were determined by real-time PCR. Treatment with OE decreased the expression of 232 genes and up-regulated 75 other genes in mesenteric white adipose tissue. The use of real-time PCR validate that, in mesenteric white adipose tissue, mRNA levels for Lipoprotein Lipase (LPL were decreased by 52%, those of Fatty Acid Synthase (FAS by 95%, those of Hormone Sensible Lipase (HSL by 32%, those of Acetyl CoA Carboxylase (ACC by 92%, those of Carnitine Palmitoyltransferase 1b (CPT1b by 45%, and those of Fatty Acid Transport Protein 1 (FATP1 and Adipocyte Fatty Acid Binding Protein (FABP4 by 52% and 49%, respectively. Conversely, Tumour Necrosis Factor (TNFα values showed overexpression (198%. Conclusion Short-term treatment with OE affects adipose tissue capacity to extract fatty acids from lipoproteins and to deal with fatty acid transport and metabolism.

  12. [Nonfasting triglycerides and risk of ischemic stroke--secondary publication

    DEFF Research Database (Denmark)

    Freiberg, J.J.; Tybjaerg-Hansen, A.; Jensen, J.S.;

    2009-01-01

    The role of triglycerides in the risk of ischemic stroke remains controversial. We tested the hypothesis that increased levels of nonfasting triglycerides are associated with ischemic stroke in the general population. Men with a nonfasting triglyceride level 5 mmol/l had a multivariable, adjusted...... hazard ratio for ischemic stroke of 2.5 (95% confidence interval: 1.3-4.8) compared with men with a nonfasting triglyceride level triglycerides is associated with risk of ischemic stroke Udgivelsesdato...

  13. Ikkefastende triglycerider og risiko for iskamisk apopleksi--sekundaerpublikation

    DEFF Research Database (Denmark)

    Freiberg, Jacob J; Tybjaerg-Hansen, Anne; Jensen, Jan Skov;

    2009-01-01

    The role of triglycerides in the risk of ischemic stroke remains controversial. We tested the hypothesis that increased levels of nonfasting triglycerides are associated with ischemic stroke in the general population. Men with a nonfasting triglyceride level 5 mmol/l had a multivariable, adjusted...... hazard ratio for ischemic stroke of 2.5 (95% confidence interval: 1.3-4.8) compared with men with a nonfasting triglyceride level triglycerides is associated with risk of ischemic stroke...

  14. BMP7 Activates Brown Adipose Tissue and Reduces Diet-Induced Obesity Only at Subthermoneutrality

    Science.gov (United States)

    Boon, Mariëtte R.; van den Berg, Sjoerd A. A.; Wang, Yanan; van den Bossche, Jan; Karkampouna, Sofia; Bauwens, Matthias; De Saint-Hubert, Marijke; van der Horst, Geertje; Vukicevic, Slobodan; de Winther, Menno P. J.; Havekes, Louis M.; Jukema, J. Wouter; Tamsma, Jouke T.; van der Pluijm, Gabri; van Dijk, Ko Willems; Rensen, Patrick C. N.

    2013-01-01

    Background/Aims Brown adipose tissue (BAT) dissipates energy stored in triglycerides as heat via the uncoupling protein UCP-1 and is a promising target to combat hyperlipidemia and obesity. BAT is densely innervated by the sympathetic nervous system, which increases BAT differentiation and activity upon cold exposure. Recently, Bone Morphogenetic Protein 7 (BMP7) was identified as an inducer of BAT differentiation. We aimed to elucidate the role of sympathetic activation in the effect of BMP7 on BAT by treating mice with BMP7 at varying ambient temperature, and assessed the therapeutic potential of BMP7 in combating obesity. Methods and Results High-fat diet fed lean C57Bl6/J mice were treated with BMP7 via subcutaneous osmotic minipumps for 4 weeks at 21°C or 28°C, the latter being a thermoneutral temperature in which sympathetic activation of BAT is largely diminished. At 21°C, BMP7 increased BAT weight, increased the expression of Ucp1, Cd36 and hormone-sensitive lipase in BAT, and increased total energy expenditure. BMP7 treatment markedly increased food intake without affecting physical activity. Despite that, BMP7 diminished white adipose tissue (WAT) mass, accompanied by increased expression of genes related to intracellular lipolysis in WAT. All these effects were blunted at 28°C. Additionally, BMP7 resulted in extensive ‘browning’ of WAT, as evidenced by increased expression of BAT markers and the appearance of whole clusters of brown adipocytes via immunohistochemistry, independent of environmental temperature. Treatment of diet-induced obese C57Bl6/J mice with BMP7 led to an improved metabolic phenotype, consisting of a decreased fat mass and liver lipids as well as attenuated dyslipidemia and hyperglycemia. Conclusion Together, these data show that BMP7-mediated recruitment and activation of BAT only occurs at subthermoneutral temperature, and is thus likely dependent on sympathetic activation of BAT, and that BMP7 may be a promising tool to

  15. The complete digestion of human milk triacylglycerol in vitro requires gastric lipase, pancreatic colipase-dependent lipase, and bile salt-stimulated lipase.

    OpenAIRE

    Bernbäck, S; Bläckberg, L; Hernell, O

    1990-01-01

    Gastric lipase, pancreatic colipase-dependent lipase, and bile salt-stimulated lipase all have potential roles in digestion of human milk triacylglycerol. To reveal the function of each lipase, an in vitro study was carried out with purified lipases and cofactors, and with human milk as substrate. Conditions were chosen to resemble those of the physiologic environment in the gastrointestinal tract of breast-fed infants. Gastric lipase was unique in its ability to initiate hydrolysis of milk t...

  16. Central nervous system control of triglyceride metabolism

    NARCIS (Netherlands)

    Geerling, Johanna Janetta (Janine)

    2013-01-01

    This thesis describes the role of the brain in the regulation of peripheral triglyceride metabolism, in the context of the metabolic syndrome. Based on various pharmacological studies we described the role of two hormones, insulin and glucagon-like peptide-1, in the production and clearance of trigl

  17. Lipoprotein lipase expression exclusively in liver. A mouse model for metabolism in the neonatal period and during cachexia.

    OpenAIRE

    Merkel, M.; Weinstock, P H; Chajek-Shaul, T; Radner, H; B. Yin; Breslow, J L; Goldberg, I J

    1998-01-01

    Lipoprotein lipase (LPL), the rate-limiting enzyme in triglyceride hydrolysis, is normally not expressed in the liver of adult humans and animals. However, liver LPL is found in the perinatal period, and in adults it can be induced by cytokines. To study the metabolic consequences of liver LPL expression, transgenic mice producing human LPL specifically in the liver were generated and crossed onto the LPL knockout (LPL0) background. LPL expression exclusively in liver rescued LPL0 mice from n...

  18. Control of adipose tissue lipolysis in ectotherm vertebrates.

    Science.gov (United States)

    Migliorini, R H; Lima-Verde, J S; Machado, C R; Cardona, G M; Garofalo, M A; Kettelhut, I C

    1992-10-01

    Lipolytic activity of fish (Hoplias malabaricus), toad (Bufo paracnemis), and snake (Philodryas patagoniensis) adipose tissue was investigated in vivo and in vitro. Catecholamines or glucagon did not affect the release of free fatty acids (FFA) by incubated fish and toad adipose tissue. Catecholamines also failed to activate snake adipose tissue lipolysis, which even decreased in the presence of epinephrine. However, glucagon stimulated both the lipolytic activity of reptilian tissue in vitro and the mobilization of FFA to plasma when administered to snakes in vivo. The release of FFA from incubated fish, amphibian, and reptilian adipose tissue increased markedly in the presence of cAMP or xanthine derivatives, inhibitors of phosphodiesterase. Forskolin or fluoride, activators of specific components of the adenylate cyclase system, strongly stimulated toad adipose tissue lipolysis. The data suggest that adipocyte triacylglycerol lipase of ectotherm vertebrates is activated by a cAMP-mediated phosphorylation and that the organization of the membrane-bound adenylate cyclase system is similar to that of mammals. PMID:1329567

  19. Structural studies on lipoprotein lipase

    International Nuclear Information System (INIS)

    The structure of lipoprotein lipase is not known. The lack of information on its primary sequence has been due to the inability of preparing it in homogeneous and stable form. This research has focused on the structural characterization of lipoprotein lipase. The first approach taken was to develop a purification method using bovine milk and affinity chromatography on heparin-Sepharose. The protein obtained was a heterogeneous peak with the activity shifted towards the trailing edge fractions. These fractions only presented a 55 Kdalton band on polyacrylamide gel electrophoresis. Monoclonal antibodies against this band detected an endogenous, phenyl methane sulfonyl fluoride-sensitive protease responsible for the presence of lower molecular weight fragments. The second approach was to label the lipoprotein lipase with a radioactive, active site, directed probe. After incubation and affinity chromatography a complex [3H]inhibitor enzyme was isolated with a stoichiometry of 1.00 +/- 0.2. The complex was digested with CNBr and the insoluble peptides at low ionic strength (>90% [3H]dpm) were used for further purification. Differential extraction of the [3H]-peptide, digestion with S. aureus V8 protease, and high performance liquid chromatography yielded a hexapeptide with a composition consistent with the consensus sequence of the active site peptides of many serine-esterase. This and the kinetic data imply this being the mechanism of action for lipoprotein lipase

  20. The galactolipase activity of Fusarium solani (phospho)lipase.

    Science.gov (United States)

    Jallouli, Raida; Othman, Houcemeddine; Amara, Sawsan; Parsiegla, Goetz; Carriere, Frédéric; Srairi-Abid, Najet; Gargouri, Youssef; Bezzine, Sofiane

    2015-03-01

    The purified (phospho)lipase of Fusarium solani (FSL), was known to be active on both triglycerides and phospholipids. This study aimed at assessing the potential of this enzyme in hydrolyzing galactolipids. FSL was found to hydrolyze at high rates of synthetic medium chains monogalactosyldiacylglycerol (4658±146U/mg on DiC8-MGDG) and digalactosyldiacylglycerol (3785±83U/mg on DiC8-DGDG) and natural long chain monogalactosyldiacylglycerol extracted from leek leaves (991±85U/mg). It is the microbial enzyme with the highest activity on galactolipids identified so far with a level of activity comparable to that of pancreatic lipase-related protein 2. FSL maximum activity on galactolipids was measured at pH8. The analysis of the hydrolysis product of natural MGDG from leek showed that FSL hydrolyzes preferentially the ester bond at the sn-1 position of galactolipids. To investigate the structure-activity relationships of FSL, a 3D model of this enzyme was built. In silico docking of medium chains MGDG and DGDG and phospholipid in the active site of FSL reveals structural solutions which are in concordance with in vitro tests.

  1. Lipase biofilm deposited by Matrix Assisted Pulsed Laser Evaporation technique

    Science.gov (United States)

    Aronne, Antonio; Bloisi, Francesco; Calabria, Raffaela; Califano, Valeria; Depero, Laura E.; Fanelli, Esther; Federici, Stefania; Massoli, Patrizio; Vicari, Luciano R. M.

    2015-05-01

    Lipase is an enzyme that finds application in biodiesel production and for detection of esters and triglycerides in biosensors. Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique derived from Pulsed Laser Deposition (PLD) for deposition of undamaged biomolecules or polymers, is characterized by the use of a frozen target obtained from a solution/suspension of the guest material (to be deposited) in a volatile matrix (solvent). The presence of the solvent avoids or at least reduces the potential damage of guest molecules by laser radiation but only the guest material reaches the substrate in an essentially solvent-free deposition. MAPLE can be used for enzymes immobilization, essential for industrial application, allowing the development of continuous processes, an easier separation of products, the reuse of the catalyst and, in some cases, enhancing enzyme properties (pH, temperature stability, etc.) and catalytic activity in non-aqueous media. Here we show that MAPLE technique can be used to deposit undamaged lipase and that the complex structure (due to droplets generated during extraction from target) of the deposited material can be controlled by changing the laser beam fluence.

  2. The galactolipase activity of Fusarium solani (phospho)lipase.

    Science.gov (United States)

    Jallouli, Raida; Othman, Houcemeddine; Amara, Sawsan; Parsiegla, Goetz; Carriere, Frédéric; Srairi-Abid, Najet; Gargouri, Youssef; Bezzine, Sofiane

    2015-03-01

    The purified (phospho)lipase of Fusarium solani (FSL), was known to be active on both triglycerides and phospholipids. This study aimed at assessing the potential of this enzyme in hydrolyzing galactolipids. FSL was found to hydrolyze at high rates of synthetic medium chains monogalactosyldiacylglycerol (4658±146U/mg on DiC8-MGDG) and digalactosyldiacylglycerol (3785±83U/mg on DiC8-DGDG) and natural long chain monogalactosyldiacylglycerol extracted from leek leaves (991±85U/mg). It is the microbial enzyme with the highest activity on galactolipids identified so far with a level of activity comparable to that of pancreatic lipase-related protein 2. FSL maximum activity on galactolipids was measured at pH8. The analysis of the hydrolysis product of natural MGDG from leek showed that FSL hydrolyzes preferentially the ester bond at the sn-1 position of galactolipids. To investigate the structure-activity relationships of FSL, a 3D model of this enzyme was built. In silico docking of medium chains MGDG and DGDG and phospholipid in the active site of FSL reveals structural solutions which are in concordance with in vitro tests. PMID:25529980

  3. [Human brown adipose tissue].

    Science.gov (United States)

    Virtanen, Kirsi A; Nuutila, Pirjo

    2015-01-01

    Adult humans have heat-producing and energy-consuming brown adipose tissue in the clavicular region of the neck. There are two types of brown adipose cells, the so-called classic and beige adipose cells. Brown adipose cells produce heat by means of uncoupler protein 1 (UCP1) from fatty acids and sugar. By applying positron emission tomography (PET) measuring the utilization of sugar, the metabolism of brown fat has been shown to multiply in the cold, presumably influencing energy consumption. Active brown fat is most likely present in young adults, persons of normal weight and women, least likely in obese persons.

  4. Targeted disruption of hormone-sensitive lipase results in male sterility and adipocyte hypertrophy, but not in obesity

    OpenAIRE

    Osuga, Jun-ichi; Ishibashi, Shun; Oka, Teruaki; Yagyu, Hiroaki; Tozawa, Ryuichi; Fujimoto, Akihisa; Shionoiri, Futoshi; Yahagi, Naoya; Kraemer, Frederic B.; Tsutsumi, Osamu; Yamada, Nobuhiro

    2000-01-01

    Hormone-sensitive lipase (HSL) is known to mediate the hydrolysis not only of triacylglycerol stored in adipose tissue but also of cholesterol esters in the adrenals, ovaries, testes, and macrophages. To elucidate its precise role in the development of obesity and steroidogenesis, we generated HSL knockout mice by homologous recombination in embryonic stem cells. Mice homozygous for the mutant HSL allele (HSL−/−) were superficially normal except that the males were...

  5. Immobilization of lipase and keratinase on functionalized SBA-15 nanostructured materials

    Science.gov (United States)

    Le, Hy G.; Vu, Tuan A.; Tran, Hoa T. K.; Dang, Phuong T.

    2013-12-01

    SBA-15 nanostructured materials were synthesized via hydrothermal treatment and were functionalized with 3- aminopropyltriethoxysilane (APTES). The obtained samples were characterized by different techniques such as XRD, BET, TEM, IR and DTA. After functionalization, it showed that these nanostrucrured materials still maintained the hexagonal pore structure of the parent SBA-15. The model enzyms chosen in this study were lipase and keratinase. Lipase was a biocatalyst for hydrolyzation of long chain triglycerides or methyl esters of long chain alcohols and fatty acids; keratinase is a proteolytic enzyme that catalyzes the cleavage of keratin. The functionalized SBA-15 materials were used to immobilize lipase and keratinase, exhibiting higher activity than that of the unfunctionalized pure silica SBA-15 ones. This might be due to the enhancing of surface hydrophobicity upon functionalization. The surface functionalization of the nanostructured silicas with organic groups can favor the interaction between enzyme and the supports and consequently increasing the operational stability of the immobilized enzymes. The loading of lipase on functionalized SBA-15 materials was higher than that of keratinase. This might be rationalized by the difference in size of enzyms.

  6. m-DOPA addition in MAPLE immobilization of lipase for biosensor applications

    Directory of Open Access Journals (Sweden)

    Valeria Califano

    2015-12-01

    Full Text Available Matrix Assisted Pulsed Laser Evaporation (MAPLE is a thin film deposition technique which uses a pulsed laser beam impinging, inside a high vacuum chamber, on a frozen target containing the guest molecules in a volatile matrix to induce fast “evaporation” of the matrix, and ejection of the guest molecules. Lipase, an enzyme acting as a catalyst in hydrolysis of lipids, is widely used in biosensors for detection of triglycerides in blood serum. A key action to this purpose is lipase immobilization on a substrate. In a recent paper, we have shown that MAPLE technique is able to deposit lipase on a substrate in an active form. Here we show that addition to the guest/matrix target of a small amount of m-DOPA (3-(3,4-dihydroxyphenyl-2-methyl-l-alanine in order to improve adhesion and protect lipase secondary structure, also allows the lowering the laser pulse energy required for matrix evaporation and therefore the risk of damaging the enzyme.

  7. Use of Mucor miehei lipase to improve functional properties of yolk-contaminated egg whites.

    Science.gov (United States)

    Macherey, Laura N; Conforti, Frank D; Eigel, William; O'Keefe, Sean F

    2011-05-01

    Egg yolk contamination of egg whites continues to be a serious problem in the egg industry. The ability of egg whites to form stable and voluminous foams is greatly inhibited by yolk contamination, even at very low levels, between 0.01% and 0.2% w/w yolk in white. Experiments were conducted to determine if Mucor miehei lipase could regenerate the functional properties of yolk-contaminated egg whites. Lipase from M. miehei and colipase from porcine pancreas were added to yolk-contaminated (0.2%, w/w) egg white samples to hydrolyze triglycerides originating from egg yolk. Enzymatic hydrolysis of triacylglycerols was confirmed using thin-layer chromatography. Treatment of yolk-contaminated samples with lipase and colipase yielded significant (P Enzyme-treated yolk-contaminated egg whites were also tested in angel food cakes. Enzyme-treated, yolk-contaminated egg whites performed similarly to non-yolk-contaminated control, and much better than yolk-contaminated sample in angel food cakes. The results show that most negative effects of yolk contamination can be reversed by treatment with Mucor miehei lipase and colipase.

  8. Lipase immobilization for catalytic applications obtained using fumed silica deposited with MAPLE technique

    Science.gov (United States)

    Bloisi, Francesco; Califano, Valeria; Perretta, Giuseppe; Nasti, Libera; Aronne, Antonio; Di Girolamo, Rocco; Auriemma, Finizia; De Rosa, Claudio; Vicari, Luciano R. M.

    2016-06-01

    Lipases are enzymes used for catalyzing reactions of acylglycerides in biodiesel production from lipids, where enzyme immobilization on a substrate is required. Silica nanoparticles in different morphologies and configurations are currently used in conjunction with biological molecules for drug delivery and catalysis applications, but up to date their use for triglycerides has been limited by the large size of long-chain lipid molecules. Matrix assisted pulsed laser evaporation (MAPLE), a laser deposition technique using a frozen solution/suspension as a target, is widely used for deposition of biomaterials and other delicate molecules. We have carried out a MAPLE deposition starting from a frozen mixture containing fumed silica and lipase in water. Deposition parameters were chosen in order to increase surface roughness and to promote the formation of complex structures. Both the target (a frozen thickened mixture of nanoparticles/catalyst in water) and the deposition configuration (a small target to substrate distance) are unusual and have been adopted in order to increase surface contact of catalyst and to facilitate access to long-chain molecules. The resulting innovative film morphology (fumed silica/lipase cluster level aggregation) and the lipase functionality (for catalytic biodiesel production) have been studied by FESEM, FTIR and transesterification tests.

  9. Diet and the role of lipoproteins, lipases, and thyroid hormones in coronary lesion growth

    Science.gov (United States)

    Barth, Jacques D.; Jansen, Hans; Reiber, Johan H. C.; Birkenhager, Jan C.; Kromhout, Daan

    1987-01-01

    The relationships between the coronary lesion growth and the blood contents of lipoprotein fractions, thyroic hormones, and the lipoprotein lipase activity were investigated in male patients with severe coronary atherosclerosis, who participated in a lipid-lowering dietary intervention program. A quantitative computer-assisted image-processing technique was used to assess the severity of coronary obstructions at the beginning of the program and at its termination two years later. Based on absolute coronary scores, patients were divided into a no-lesion growth group (14 patients) and a progression group (21 paients). At the end of the trial, the very-low-density lipoprotein cholesterol and triglycerides were found to be significantly higher, while the high-density lipoprotein cholesterol and hepatic lipase (HL) were lower in the progression group. Multivariate regression analysis showed HL to be the most important determinant of changes in coronary atherosclerotic lesions.

  10. The Role of Triglycerides in Atherosclerosis

    OpenAIRE

    Talayero, Beatriz G.; Sacks, Frank M.

    2011-01-01

    Hypertriglyceridemia is a prevalent risk factor for cardiovascular disease (CVD) and increasingly important in the setting of current obesity and insulin resistance epidemics. High triglyceride (TG) levels are markers for several types of atherogenic lipoproteins. Patients who have hypertriglyceridemia may be at significant risk for CVD even if low-density lipoprotein cholesterol levels are at goal, and therefore warrant treatment that optimizes diet, reduces overweight, and promotes regular ...

  11. MICROBIAL LIPASES: PRODUCTION OF EXTRACELLULAR LIPASE ENZYME BY ALCALIGENES VISCOSUS (DOGE-1) STRAIN

    OpenAIRE

    P.Sekhar

    2012-01-01

    Industrially important extracellular lipase enzyme production was explored by utilizingmicrobial strain isolated from dairy effluents. Alcaligenes viscosus DOGE-1 strain isolated from dairywaste waters proved to produce extracellular lipase. Various growth factors were attempted to maximizethe lipase production by this strain. Growth factors like NH4PO4, Peptone, Urea coupled with peptone,KH2PO4, Olive oil and pH were found to be favored the maximum lipase production. This microbialstrain was...

  12. Adipose tissue macrophages

    NARCIS (Netherlands)

    Boutens, Lily; Stienstra, Rinke

    2016-01-01

    Inflammation originating from the adipose tissue is considered to be one of the main driving forces for the development of insulin resistance and type 2 diabetes in obese individuals. Although a plethora of different immune cells shapes adipose tissue inflammation, this review is specifically foc

  13. Regulation of Lipolysis and Adipose Tissue Signaling during Acute Endotoxin-Induced Inflammation

    DEFF Research Database (Denmark)

    Rittig, Nikolaj; Bach, Ermina; Thomsen, Henrik Holm;

    2016-01-01

    = 0.001) compared with Placebo. These effects were associated with increased phosphorylation of hormone sensitive lipase (pHSL) at ser650 in adipose tissue (p = 0.03), a trend towards elevated pHSL at ser552 (p = 0.09) and cAMP-dependent protein kinase A (PKA) phosphorylation of perilipin 1 (PLIN1) (p...... lipolysis in adipose tissue and is associated with increased pHSL and signs of increased PLIN1 phosphorylation combined with a trend toward decreased insulin signaling. The combination of these mechanisms appear to be the driving forces behind the increased lipolysis observed in the early stages of acute...

  14. Serum pancreatic lipase activity in cystic fibrosis.

    OpenAIRE

    Junglee, D; Penketh, A; Katrak, A; Hodson, M.E.; Batten, J C; Dandona, P

    1983-01-01

    Patients with cystic fibrosis have been found to have abnormal serum concentrations of immunoreactive trypsin and abnormal activities of pancreatic isoamylase. A study was undertaken to discover whether activity of pancreatic lipase is also altered in cystic fibrosis. Serum from 23 patients with cystic fibrosis was assayed for immunoreactive trypsin and pancreatic lipase. Median serum pancreatic lipase activity was significantly lower in patients with cystic fibrosis than in controls, as was ...

  15. Anti-obesity effect of Dioscorea nipponica Makino with lipase-inhibitory activity in rodents.

    Science.gov (United States)

    Kwon, Chong-Suk; Sohn, Ho Yong; Kim, Sung Hee; Kim, Ji Hyun; Son, Kun Ho; Lee, Jeong Soon; Lim, Jin Kyu; Kim, Jong-Sang

    2003-07-01

    In the process of screening for pancreatic lipase inhibitors, which could be used as an anti-obesity measure, the methanol extract of Dioscorea nipponica Makino powder (DP) appeared to have potent inhibitory activity against porcine pancreatic lipase with an IC50 value of 5-10 microg/ml, where the enzyme activity was assayed by using 4-methylumbelliferyl oleate as a substrate. Further purification of active components present in the herb generated dioscin that belongs to the saponin family. Dioscin and its aglycone, diosgenin, both suppressed the time-dependent increase of blood triacylglycerol level when orally injected with corn oil to mice, suggesting their inhibitory potential against fat absorption. Sprague-Dawley rats fed on a high-fat diet containing 5% Dioscorea nipponica Makino and 40% beef tallow gained significantly less body weight and adipose tissue than control animals fed on a high-fat diet alone during an 8-week experimental period (P<0.05). PMID:12913286

  16. Nonfasting triglycerides, cholesterol, and ischemic stroke in the general population

    DEFF Research Database (Denmark)

    Varbo, Anette; Nordestgaard, Børge G; Tybjaerg-Hansen, Anne;

    2011-01-01

    Current guidelines on stroke prevention have recommendations on desirable cholesterol levels, but not on nonfasting triglycerides. We compared stepwise increasing levels of nonfasting triglycerides and cholesterol for their association with risk of ischemic stroke in the general population....

  17. Production of an acidic and thermostable lipase of the mesophilic fungus Penicillium simplicissimum by solid-state fermentation.

    Science.gov (United States)

    Gutarra, Melissa L E; Godoy, Mateus G; Maugeri, Francisco; Rodrigues, Maria Isabel; Freire, Denise M G; Castilho, Leda R

    2009-11-01

    The production of a lipase by a wild-type Brazilian strain of Penicillium simplicissimum in solid-state fermentation of babassu cake, an abundant residue of the oil industry, was studied. The enzyme production reached about 90 U/g in 72 h, with a specific activity of 4.5 U/mg of total proteins. The crude lipase showed high activities at 35-60 degrees C and pH 4.0-6.0, with a maximum activity at 50 degrees C and pH 4.0-5.0. Enzyme stability was enhanced at pH 5.0 and 6.0, with a maximum half-life of 5.02 h at 50 degrees C and pH 5.0. Thus, this lipase shows a thermophilic and thermostable behavior, what is not common among lipases from mesophilic filamentous fungi. The crude enzyme catalysed the hydrolysis of triglycerides and p-nitrophenyl esters (C4:0-C18:0), preferably acting on substrates with medium-chain fatty acids. This non-purified lipase in addition to interesting properties showed a reduced production cost making feasible its applicability in many fields. PMID:19560339

  18. Study of Antiobesity Effect through Inhibition of Pancreatic Lipase Activity of Diospyros kaki Fruit and Citrus unshiu Peel

    Science.gov (United States)

    Kim, Gyo-Nam; Shin, Mi-Rae; Shin, Sung Ho; Lee, Ah Reum; Lee, Joo Young; Seo, Bu-Il; Kim, Min Yeong; Kim, Tae Hoon; Noh, Jeong Sook; Rhee, Man Hee

    2016-01-01

    Pancreatic lipase is the enzyme responsible for digestion and absorption of triglycerides, being its inhibition one of the widest studied methods used to determine the potential activity of natural products to inhibit dietary fat absorption. Decrease of energy intake from dietary fat through inhibition of this enzyme may be an excellent strategy to prevent and treat obesity. The inhibitory activity on pancreatic lipase enzyme of Diospyros kaki fruit and Citrus unshiu peel mixture extract (PCM) was evaluated in vitro and its antiobesity effects were studied based on the serum lipid parameters analysis from high-fat diet- (HFD-) fed mice in vivo. PCM was orally administered at a dose of 50 and 200 mg/kg body weight for 6 weeks. In addition, the activity of pancreatic lipase was assessed using orlistat (positive control). PCM exhibited inhibitory effect on lipase activity with IC50 value of 507.01 μg/mL. Moreover, serum triacylglycerol, total cholesterol levels, and visceral fat weight were significantly reduced compared to HFD control mice in PCM 200 mg/kg-treated mice (p absorption via inhibition of pancreatic lipase. PMID:27529064

  19. Botulinum toxin injections to reduce adiposity: possibility, or fat chance?

    Science.gov (United States)

    Lim, Erle C H; Seet, Raymond C S

    2006-01-01

    Obese individuals often suffer from negative self-image. Many, even those with a normal body mass index, resort to pharmacotherapy (lipase inhibitors or appetite suppressants), mesotherapy and surgery (gastric volume reduction, liposuction or apronectomy) in a bid to remove excess adipose tissue. These treatments are associated with inherent morbidity and even mortality, and hence should not be undertaken lightly. The observation that denervation of adipose tissue results in lipoatrophy leads us to postulate that chemodenervation using botulinum toxin may achieve the same result, i.e. fat loss, and we explore the methods by which selective fat loss may be achieved. We concede that removal of subcutaneous fat does not, however, reduce the risks associated with the metabolic syndrome, as visceral (intra-abdominal) fat is not reduced by the removal of subcutaneous fat. PMID:16716533

  20. Lipase turbidimetric assay and acute pancreatitis.

    Science.gov (United States)

    Orda, R; Orda, S; Baron, J; Wiznitzer, T

    1984-04-01

    The simplified turbidimetric assay for lipase activity was used for the differential diagnosis of acute pancreatitis. Serum lipase levels were found to be increased in a group of 17 patients in whom acute pancreatitis was clinically suspected and confirmed by a high ACCR and decreased uptake of the radionuclide in the pancreas scan. The lipase levels were within normal limits in a control group of 14 patients suffering from diseases other than acute pancreatitis. The turbidimetric test was helpful for rapid quantitative determination of serum lipase and thus for the early and accurate diagnosis of acute pancreatitis. PMID:6200277

  1. Glycogen shortage during fasting triggers liver–brain–adipose neurocircuitry to facilitate fat utilization

    Science.gov (United States)

    Izumida, Yoshihiko; Yahagi, Naoya; Takeuchi, Yoshinori; Nishi, Makiko; Shikama, Akito; Takarada, Ayako; Masuda, Yukari; Kubota, Midori; Matsuzaka, Takashi; Nakagawa, Yoshimi; Iizuka, Yoko; Itaka, Keiji; Kataoka, Kazunori; Shioda, Seiji; Niijima, Akira; Yamada, Tetsuya; Katagiri, Hideki; Nagai, Ryozo; Yamada, Nobuhiro; Kadowaki, Takashi; Shimano, Hitoshi

    2013-01-01

    During fasting, animals maintain their energy balance by shifting their energy source from carbohydrates to triglycerides. However, the trigger for this switch has not yet been entirely elucidated. Here we show that a selective hepatic vagotomy slows the speed of fat consumption by attenuating sympathetic nerve-mediated lipolysis in adipose tissue. Hepatic glycogen pre-loading by the adenoviral overexpression of glycogen synthase or the transcription factor TFE3 abolished this liver–brain–adipose axis activation. Moreover, the blockade of glycolysis through the knockdown of the glycogen phosphorylase gene and the resulting elevation in the glycogen content abolished the lipolytic signal from the liver, indicating that glycogen is the key to triggering this neurocircuitry. These results demonstrate that liver glycogen shortage activates a liver–brain–adipose neural axis that has an important role in switching the fuel source from glycogen to triglycerides under prolonged fasting conditions. PMID:23939267

  2. VLDL hydrolysis by hepatic lipase regulates PPARδ transcriptional responses.

    Directory of Open Access Journals (Sweden)

    Jonathan D Brown

    Full Text Available BACKGROUND: PPARs (α,γ,δ are a family of ligand-activated transcription factors that regulate energy balance, including lipid metabolism. Despite these critical functions, the integration between specific pathways of lipid metabolism and distinct PPAR responses remains obscure. Previous work has revealed that lipolytic pathways can activate PPARs. Whether hepatic lipase (HL, an enzyme that regulates VLDL and HDL catabolism, participates in PPAR responses is unknown. METHODS/PRINCIPAL FINDINGS: Using PPAR ligand binding domain transactivation assays, we found that HL interacted with triglyceride-rich VLDL (>HDL≫LDL, IDL to activate PPARδ preferentially over PPARα or PPARγ, an effect dependent on HL catalytic activity. In cell free ligand displacement assays, VLDL hydrolysis by HL activated PPARδ in a VLDL-concentration dependent manner. Extended further, VLDL stimulation of HL-expressing HUVECs and FAO hepatoma cells increased mRNA expression of canonical PPARδ target genes, including adipocyte differentiation related protein (ADRP, angiopoietin like protein 4 and pyruvate dehydrogenase kinase-4. HL/VLDL regulated ADRP through a PPRE in the promoter region of this gene. In vivo, adenoviral-mediated hepatic HL expression in C57BL/6 mice increased hepatic ADRP mRNA levels by 30%. In ob/ob mice, a model with higher triglycerides than C57BL/6 mice, HL overexpression increased ADRP expression by 70%, demonstrating the importance of triglyceride substrate for HL-mediated PPARδ activation. Global metabolite profiling identified HL/VLDL released fatty acids including oleic acid and palmitoleic acid that were capable of recapitulating PPARδ activation and ADRP gene regulation in vitro. CONCLUSIONS: These data define a novel pathway involving HL hydrolysis of VLDL that activates PPARδ through generation of specific monounsaturated fatty acids. These data also demonstrate how integrating cell biology with metabolomic approaches provides insight

  3. Relationship between two common lipoprotein lipase variants and the metabolic syndrome and its individual components

    DEFF Research Database (Denmark)

    Vishram, Julie K K; Hansen, Tine W; Torp-Pedersen, Christian;

    2016-01-01

    BACKGROUND: Common lipoprotein lipase (LPL) variants are important determinants of triglycerides (TG) and high-density lipoprotein (HDL) cholesterol (C) concentrations. High TG/low HDL-C tend to cluster with hypertension, glucose intolerance, and abdominal obesity and comprise the metabolic...... syndrome (MetS). The role of LPL variants as a cause of MetS is unclear. This study investigated the relationship between two common LPL variants and the presence of MetS and its individual components. METHODS: Cross-sectional study, including 2348 Danish women (50.7%) and men, age 41-72 years, without...

  4. Lipase Activity of Guinea Pig Peritoneal Macrophages and Mycobacterial Lipase Inhibitor

    OpenAIRE

    Kiyotani, Katsuhiro; Tasaka, Hiromichi; Tsukiyama, Fumiaki; Matsuo, Yoshiyasu

    1983-01-01

    The interaction of mycobacterial lipase inhibitor (MLI), isolated from culture supernatant fluid of Mycobacterium tuberculosis strain H37Rv, and lipase from guinea pig peritoneal macrophages (GP-PMφs) was investigated fluorimetrically by the modified lipase assay system which had previously been proposed. Two peaks of lipase activity were observed in the enzyme preparation from GPPMφs. The activity of MLI against lipase from GP-PMφs was significantly high at acidic pH less than 5.0, and t...

  5. [TOTAL PARENTERAL NUTRITION IN A PREGNANT PATIENT WITH ACUTE PANCREATITIS AND LIPOPROTEIN LIPASE DEFICIENCY].

    Science.gov (United States)

    Contreras-Bolívar, Victoria; González-Molero, Inmaculada; Valdivieso, Pedro; Olveira, Gabriel

    2015-10-01

    We present a case of severe acute pancreatitis induced by hypertriglyceridemia secondary to lipoprotein lipase (LPL) deficiency in a pregnant patient with gestational diabetes, initially maneged with diet but it was later necessary to carry out artificial nutricional support measures: total parenteral nutrition. LPL deficiency might cause severe hypertriglyceridemia, repetition acute pancreatitis which is an unwieldy and severe situation during pregnancy. Acute familial hypertriglyceridemia pancreatitis accounts for 5% of cases, including LPL deficiency. The goal of treatment is to reach triglycerides levels below 500 mg/dl, being very low fat diet the treatment of choice, drugs or plasmapheresis techniques can also be associated. TPN enriched in ω3 fatty acids and glutamine was safe and effective in our patient with significant decrease in triglyceride levels.

  6. Lipoprotein Lipase Deficiency (R243H) in a Type 2 Diabetes Patient with Multiple Arterial Aneurysms.

    Science.gov (United States)

    Suzuki, Toru; Sawada, Shojiro; Ishigaki, Yasushi; Tsukita, Sohei; Kodama, Shinjiro; Sugisawa, Takashi; Imai, Junta; Yamada, Tetsuya; Yamaguchi, Takashi; Murano, Takeyoshi; Katagiri, Hideki

    2016-01-01

    Lipoprotein lipase (LPL) deficiency is a rare monogenic disorder that manifests as severe hypertriglyceridemia. Whether or not LPL deficiency accelerates the development of atherosclerosis remains controversial. We herein report a 66-year-old woman who was homozygous for the R243H LPL mutation. She had developed multiple arterial aneurysms and systemic atherosclerosis despite good control of other atherogenic risk factors, including diabetes. Furthermore, although intensive pharmaceutical therapies had been minimally effective, medium chain triglyceride (MCT) therapy reduced the serum triglyceride levels. Thus, this case suggests important role that mutated LPL protein plays in the progression of atherosclerosis and that MCT therapy is potentially effective, even for severe hypertriglyceridemia due to LPL deficiency. PMID:27150867

  7. Patient Guide to the Assessment and Treatment of Hypertriglyceridemia (High Triglycerides)

    Science.gov (United States)

    Assessment and Treatment of Hypertriglyceridemia (High Triglycerides) A Patient’s Guide Having high levels of triglycerides, or hypertriglyceridemia , is a common problem. Triglycerides are fats in ...

  8. Cyclic GMP signaling in cardiomyocytes modulates fatty acid trafficking and prevents triglyceride accumulation.

    Science.gov (United States)

    Khairallah, Ramzi J; Khairallah, Maya; Gélinas, Roselle; Bouchard, Bertrand; Young, Martin E; Allen, Bruce G; Lopaschuk, Gary D; Deschepper, Christian F; Des Rosiers, Christine

    2008-08-01

    While the balance between carbohydrates and fatty acids for energy production appears to be crucial for cardiac homeostasis, much remains to be learned about the molecular mechanisms underlying this relationship. Given the reported benefits of cGMP signaling on the myocardium, we investigated the impact of its chronic activation on cardiac energy metabolism using mice overexpressing a constitutively active cytoplasmic guanylate cyclase (GC(+/0)) in cardiomyocytes. Ex vivo working GC(+/0) heart perfusions with (13)C-labeled substrates revealed an altered pattern of exogenous substrate fuel selection compared to controls, namely a 38+/-9% lower contribution of exogenous fatty acids to acetyl-CoA formation, while that of carbohydrates remains unchanged despite a two-fold increase in glycolysis. The lower contribution of exogenous fatty acids to energy production is not associated with changes in energy demand or supply (contractile function, oxygen consumption, tissue acetyl-CoA or CoA levels, citric acid cycle flux rate) or in the regulation of beta-oxidation (acetyl-CoA carboxylase activity, tissue malonyl-CoA levels). However, GC(+/0) hearts show a two-fold increase in the incorporation of exogenous oleate into triglycerides. Furthermore, the following molecular data are consistent with a concomitant increase in triglyceride hydrolysis: (i) increased abundance of hormone sensitive lipase (HSL) protein (24+/-11%) and mRNA (22+/-4%) as well as (ii) several phosphorylation events related to HSL inhibitory (AMPK) and activation (ERK 1/2) sites, which should contribute to enhance its activity. These changes in exogenous fatty acid trafficking in GC(+/0) hearts appear to be functionally relevant, as demonstrated by their resistance to fasting-induced triglyceride accumulation. While the documented metabolic profile of GC(+/0) mouse hearts is partly reminiscent of hypertrophied hearts, the observed changes in lipid trafficking have not been previously documented, and may

  9. 21 CFR 184.1415 - Animal lipase.

    Science.gov (United States)

    2010-04-01

    ... Substances Affirmed as GRAS § 184.1415 Animal lipase. (a) Animal lipase (CAS Reg. No. 9001-62-1) is an enzyme preparation obtained from edible forestomach tissue of calves, kids, or lambs, or from animal pancreatic tissue. The enzyme preparation may be produced as a tissue preparation or as an aqueous extract....

  10. Organic Solvent Tolerant Lipases and Applications

    Directory of Open Access Journals (Sweden)

    Shivika Sharma

    2014-01-01

    Full Text Available Lipases are a group of enzymes naturally endowed with the property of performing reactions in aqueous as well as organic solvents. The esterification reactions using lipase(s could be performed in water-restricted organic media as organic solvent(s not only improve(s the solubility of substrate and reactant in reaction mixture but also permit(s the reaction in the reverse direction, and often it is easy to recover the product in organic phase in two-phase equilibrium systems. The use of organic solvent tolerant lipase in organic media has exhibited many advantages: increased activity and stability, regiospecificity and stereoselectivity, higher solubility of substrate, ease of products recovery, and ability to shift the reaction equilibrium toward synthetic direction. Therefore the search for organic solvent tolerant enzymes has been an extensive area of research. A variety of fatty acid esters are now being produced commercially using immobilized lipase in nonaqueous solvents. This review describes the organic tolerance and industrial application of lipases. The main emphasis is to study the nature of organic solvent tolerant lipases. Also, the potential industrial applications that make lipases the biocatalysts of choice for the present and future have been presented.

  11. Enhanced activity of hormone sensitive lipase (HSL) in mesenteric but not epididymal fat correlates with higher production of epinephrine in mesenteric adipocytes in rat model of cachectic rheumatoid arthritis.

    Science.gov (United States)

    Stofkova, Andrea; Krskova, Katarina; Vaculin, Simon; Jurcovicova, Jana

    2016-06-01

    Cachectic rheumatoid arthritis, the less frequent form of the disease, is associated with loss of fat mass and often more severe course of the disease. Its experimental model represents rat adjuvant arthritis (AA) characterized by edema, lack of appetite, sharp body weight and fat loss. As individual fat depots display functional differences, here we studied lipolytic activity and sensitivity to lipolytic stimuli of nodeless epididymal fat (eWAT) and perinodal mesenteric fat (mWAT) depots at the peak of AA. We also examined changes in catecholamine and cytokine levels involved in lipolysis in plasma and/or isolated adipocytes from both WATs to identify the contribution of local, adipocyte-based processes and/or systemic events to adiposity loss in cachectic rheumatoid arthritis. AA was induced to male Lewis rats by complete Freund's adjuvant. Groups of ad libitum-fed and pair-fed controls were used to distinguish the effects of food restriction from inflammation-induced cachexia. Adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL) and its phosphorylated form (pHSL) were analyzed by western blot. CRP and catecholamine levels in plasma or adipocyte lysates were determined using ELISA kits. Cytokine-induced neutrophil chemoattractant-1 (CINC-1/CXCL1), monocyte chemoattractant protein-1 (MCP-1/CCL2), IL-1β, IL-6, IL-10 and leptin in adipocyte lysate were analyzed by quantitative protein microarray. Plasma glycerol and FFA were measured spectrophotometrically. AA rats developed severe cachexia, with lower adiposity in mWAT compared to normal and pair-fed controls, whereas in eWAT the adiposity was similarly reduced in AA and pair-fed groups. ATGL levels in both WATs were not affected by AA or pair feeding. AA upregulated levels of HSL, pHSL and pHSL/HSL ratio in mWAT, whereas none of these parameters has changed in eWAT of AA rats or in either WATs of pair-fed rats. In AA rats plasma glycerol was elevated, whereas FFA concentration was reduced. Plasma

  12. Reduction of Adipose Tissue Mass by the Angiogenesis Inhibitor ALS-L1023 from Melissa officinalis.

    Directory of Open Access Journals (Sweden)

    Byung Young Park

    Full Text Available It has been suggested that angiogenesis modulates adipogenesis and obesity. This study was undertaken to determine whether ALS-L1023 (ALS prepared by a two-step organic solvent fractionation from Melissa leaves, which exhibits antiangiogenic activity, can regulate adipose tissue growth. The effects of ALS on angiogenesis and extracellular matrix remodeling were measured using in vitro assays. The effects of ALS on adipose tissue growth were investigated in high fat diet-induced obese mice. ALS inhibited VEGF- and bFGF-induced endothelial cell proliferation and suppressed matrix metalloproteinase (MMP activity in vitro. Compared to obese control mice, administration of ALS to obese mice reduced body weight gain, adipose tissue mass and adipocyte size without affecting appetite. ALS treatment decreased blood vessel density and MMP activity in adipose tissues. ALS reduced the mRNA levels of angiogenic factors (VEGF-A and FGF-2 and MMPs (MMP-2 and MMP-9, whereas ALS increased the mRNA levels of angiogenic inhibitors (TSP-1, TIMP-1, and TIMP-2 in adipose tissues. The protein levels of VEGF, MMP-2 and MMP-9 were also decreased by ALS in adipose tissue. Metabolic changes in plasma lipids, liver triglycerides, and hepatic expression of fatty acid oxidation genes occurred during ALS-induced weight loss. These results suggest that ALS, which has antiangiogenic and MMP inhibitory activities, reduces adipose tissue mass in nutritionally obese mice, demonstrating that adipose tissue growth can be regulated by angiogenesis inhibitors.

  13. Obesity, adiposity, and dyslipidemia: a consensus statement from the National Lipid Association.

    Science.gov (United States)

    Bays, Harold E; Toth, Peter P; Kris-Etherton, Penny M; Abate, Nicola; Aronne, Louis J; Brown, W Virgil; Gonzalez-Campoy, J Michael; Jones, Steven R; Kumar, Rekha; La Forge, Ralph; Samuel, Varman T

    2013-01-01

    The term "fat" may refer to lipids as well as the cells and tissue that store lipid (ie, adipocytes and adipose tissue). "Lipid" is derived from "lipos," which refers to animal fat or vegetable oil. Adiposity refers to body fat and is derived from "adipo," referring to fat. Adipocytes and adipose tissue store the greatest amount of body lipids, including triglycerides and free cholesterol. Adipocytes and adipose tissue are active from an endocrine and immune standpoint. Adipocyte hypertrophy and excessive adipose tissue accumulation can promote pathogenic adipocyte and adipose tissue effects (adiposopathy), resulting in abnormal levels of circulating lipids, with dyslipidemia being a major atherosclerotic coronary heart disease risk factor. It is therefore incumbent upon lipidologists to be among the most knowledgeable in the understanding of the relationship between excessive body fat and dyslipidemia. On September 16, 2012, the National Lipid Association held a Consensus Conference with the goal of better defining the effect of adiposity on lipoproteins, how the pathos of excessive body fat (adiposopathy) contributes to dyslipidemia, and how therapies such as appropriate nutrition, increased physical activity, weight-management drugs, and bariatric surgery might be expected to impact dyslipidemia. It is hoped that the information derived from these proceedings will promote a greater appreciation among clinicians of the impact of excess adiposity and its treatment on dyslipidemia and prompt more research on the effects of interventions for improving dyslipidemia and reducing cardiovascular disease risk in overweight and obese patients.

  14. Reduction of Adipose Tissue Mass by the Angiogenesis Inhibitor ALS-L1023 from Melissa officinalis.

    Science.gov (United States)

    Park, Byung Young; Lee, Hyunghee; Woo, Sangee; Yoon, Miso; Kim, Jeongjun; Hong, Yeonhee; Lee, Hee Suk; Park, Eun Kyu; Hahm, Jong Cheon; Kim, Jin Woo; Shin, Soon Shik; Kim, Min-Young; Yoon, Michung

    2015-01-01

    It has been suggested that angiogenesis modulates adipogenesis and obesity. This study was undertaken to determine whether ALS-L1023 (ALS) prepared by a two-step organic solvent fractionation from Melissa leaves, which exhibits antiangiogenic activity, can regulate adipose tissue growth. The effects of ALS on angiogenesis and extracellular matrix remodeling were measured using in vitro assays. The effects of ALS on adipose tissue growth were investigated in high fat diet-induced obese mice. ALS inhibited VEGF- and bFGF-induced endothelial cell proliferation and suppressed matrix metalloproteinase (MMP) activity in vitro. Compared to obese control mice, administration of ALS to obese mice reduced body weight gain, adipose tissue mass and adipocyte size without affecting appetite. ALS treatment decreased blood vessel density and MMP activity in adipose tissues. ALS reduced the mRNA levels of angiogenic factors (VEGF-A and FGF-2) and MMPs (MMP-2 and MMP-9), whereas ALS increased the mRNA levels of angiogenic inhibitors (TSP-1, TIMP-1, and TIMP-2) in adipose tissues. The protein levels of VEGF, MMP-2 and MMP-9 were also decreased by ALS in adipose tissue. Metabolic changes in plasma lipids, liver triglycerides, and hepatic expression of fatty acid oxidation genes occurred during ALS-induced weight loss. These results suggest that ALS, which has antiangiogenic and MMP inhibitory activities, reduces adipose tissue mass in nutritionally obese mice, demonstrating that adipose tissue growth can be regulated by angiogenesis inhibitors.

  15. Lipase catalyzed synthesis of aromatic esters of sugar alcohols

    NARCIS (Netherlands)

    Croitoru, R.; Broek, van den L.A.M.; Frissen, A.E.; Davidescu, C.M.; Peter, F.; Boeriu, C.G.

    2011-01-01

    Commercially available lipases (Candida antarctica lipase B, Novozyme 435, Thermomyces lanuginosus lipase, and Lipozyme TL IM), as well as sol-gel immobilized lipases, have been screened for their ability to acylate regioselectively xylitol, sorbitol, and mannitol with a phenolic ester in a binary m

  16. Cloning, purification and characterisation of Staphylococcus warneri lipase 2

    NARCIS (Netherlands)

    van Kampen, M.D.; Rosenstein, R.; Götz, F.; Egmond, M.R.

    2010-01-01

    A gene encoding an extracellular lipase was identified in Staphylococcus warneri 863. The deduced lipase is organised as a prepro-protein and has significant similarity to other staphylococcal lipases. The mature part of the lipase was expressed with an N-terminal histidine tag in Escherichia coli,

  17. LIPASES PRODUCED BY YEASTS: POWERFUL BIOCATALYSTS FOR INDUSTRIAL PURPOSES

    Directory of Open Access Journals (Sweden)

    Luiza Lux Lock

    2007-12-01

    Full Text Available The term “lipolytic enzymes” refers to the lipases and carboxylic ester hydrolases. Lipase production is widespread among yeasts, but few are capable of producing lipases with interesting characteristics and in sufficient amounts to be industrially useful. The literature concerning lipases produced by Candida rugosa, Yarrowia (Candida lipolytica, Candida antarctica and other emerging lipase-producing yeasts is reviewed. The use of recombinant lipases is discussed, with emphasis on the utilization of heterologous expression systems and design of chimeras. Finally, the three approaches that aim the improvement of lipase production or the modification of the substrate selectivity of the enzyme (medium engineering, biocatalyst engineering, and protein engineering are discussed.

  18. Carboxylesterase 1 gene duplication and mRNA expression in adipose tissue are linked to obesity and metabolic function

    DEFF Research Database (Denmark)

    Friedrichsen, Martin; Poulsen, Pernille; Wojtaszewski, Jørgen;

    2013-01-01

    involved in the control of mRNA expression. Here, we investigated mRNA expression level in adipose tissue and its association with measures of adiposity and metabolic function in a population of elderly twins. Furthermore, the heritability of mRNA expression level in adipose tissue and the effect of gene......CONTEXT AND AIMS: Carboxylesterase 1 (CES1) appears to play an important role in the control of the metabolism of triglycerides and cholesterol in adipocytes and other cell types including hepatocytes. Therefore, it is relevant to gain insights into the genetic versus non-genetic mechanisms...

  19. The photo biological effect of low level laser therapy on serum level of leptin, cholesterol and triglycerides in overweight and obese females

    International Nuclear Information System (INIS)

    The use of low level laser for body contouring and weight reduction depends on the photochemical non thermal effect of laser light on the adipose tissue. LLLT was reported to liquefy or release stored fat in adipocytes by the opening of specialized yet not identified cell membrane-associated pores after a brief treatment The concentration of leptin in adipose tissue and serum closely parallel the mass of adipose tissue and adipocyte size and triglycerides content. Thus, leptin increases in obesity and falls with weight loss. The current study was conducted to evaluate the effect of the low level laser therapy (LLLT) on leptin hormone, Cholesterol and triglyceride in both overweight and obese females. Twenty women were included in this study. Their ages ranged from 30-40 years. They were divided into two equal groups. Group A (Overweight group): included 10 females with BMI between 25 and 29.9 Kg/m2 -Group B (Obese group): included 10 females with BMI . 30. Both groups received LLL to the abdomen using laser scanner for uniform distribution of the beam above and below the umbilicus. Duration of treatment was 30 minutes, 2 times per week for 8 weeks as a total period of treatment. Serum level of leptin was estimated by radioimmunoassay (RIA). As regards serum cholesterol and triglyceride they were determined by enzymatic colorimetric test. Biochemical assessments were done before and after treatment. Results of the present study showed that in the overweight group laser treatment resulted in highly significant reduction in leptin serum level accompanied by highly significant increase in serum triglycerides level. Meanwhile, the increase in cholesterol level was insignificant. As regards the obese group, alteration in serum leptin level caused by laser treatment was not significant. In this group the increase in triglycerides and cholesterol serum levels after treatment were highly significant

  20. Visceral adiposity syndrome.

    Science.gov (United States)

    Lopes, Heno F; Corrêa-Giannella, Maria Lúcia; Consolim-Colombo, Fernanda M; Egan, Brent M

    2016-01-01

    The association of anthropometric (waist circumference) and hemodynamic (blood pressure) changes with abnormalities in glucose and lipid metabolism has been motivation for a lot of discussions in the last 30 years. Nowadays, blood pressure, body mass index/abdominal circumference, glycemia, triglyceridemia, and HDL-cholesterol concentrations are considered in the definition of Metabolic syndrome, referred as Visceral adiposity syndrome (VAS) in the present review. However, more than 250 years ago an association between visceral and mediastinal obesity with hypertension, gout, and obstructive apnea had already been recognized. Expansion of visceral adipose tissue secondary to chronic over-consumption of calories stimulates the recruitment of macrophages, which assume an inflammatory phenotype and produce cytokines that directly interfere with insulin signaling, resulting in insulin resistance. In turn, insulin resistance (IR) manifests itself in various tissues, contributing to the overall phenotype of VAS. For example, in white adipose tissue, IR results in lipolysis, increased free fatty acids release and worsening of inflammation, since fatty acids can bind to Toll-like receptors. In the liver, IR results in increased hepatic glucose production, contributing to hyperglycemia; in the vascular endothelium and kidney, IR results in vasoconstriction, sodium retention and, consequently, arterial hypertension. Other players have been recognized in the development of VAS, such as genetic predisposition, epigenetic factors associated with exposure to an unfavourable intrauterine environment and the gut microbiota. More recently, experimental and clinical studies have shown the autonomic nervous system participates in modulating visceral adipose tissue. The sympathetic nervous system is related to adipose tissue function and differentiation through beta1, beta2, beta3, alpha1, and alpha2 adrenergic receptors. The relation is bidirectional: sympathetic denervation of

  1. Lipoprotein lipase is produced, regulated, and functional in rat brain.

    OpenAIRE

    Eckel, R.H.; Robbins, R J

    1984-01-01

    Lipoprotein lipase (LP lipase, triacylglycero-protein acylhydrolase EC 3.1.1.34) activity was found in four dissimilar brain regions (hypothalamus, cortex, cerebellum, and midbrain) of adult male rats. Progressive accumulation of LP lipase activity in cultured fetal rat hypothalamic cells was also observed, indicating de novo synthesis of the lipase. The brain LP lipase activity was serum-dependent and was inhibited by 1 M NaCl and by protamine sulfate. Kinetic analysis revealed an apparent K...

  2. Neutrophil chemotaxis by Propionibacterium acnes lipase and its inhibition.

    OpenAIRE

    Lee, W. L.; Shalita, A R; Suntharalingam, K; Fikrig, S M

    1982-01-01

    The chemoattraction of Propionibacterium acnes lipase for neutrophils and the effect of lipase inhibitor and two antibiotic agents on the chemotaxis were evaluated. Of the various fractions tested, partially purified lipase (fraction 2c) was the most active cytotaxin produced by P. acnes. Serum mediators were not required for the generation of chemotaxis by lipase in vitro. Diisopropyl phosphofluoridate at low concentration (10(-4) mM) completely inhibited lipase activity as well as polymorph...

  3. Cultured human astrocytes secrete large cholesteryl ester- andtriglyceride-rich lipoproteins along with endothelial lipase

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lin; Liu, Yanzhu; Forte, Trudy M.; Chisholm, Jeffrey W.; Parks, John S.; Shachter, Neil S.

    2003-12-01

    We cultured normal human astrocytes and characterized their secreted lipoproteins. Human astrocytes secreted lipoproteins in the size range of plasma VLDL (Peak 1), LDL (Peak 2), HDL (Peak 3) and a smaller peak (Peak 4), as determined by gel filtration chromatography, nondenaturing gradient gel electrophoresis and transmission electron microscopy. Cholesterol enrichment of astrocytes led to a particular increase in Peak 1. Almost all Peak 2, 3 and 4 cholesterol and most Peak 1 cholesterol was esterified (unlike mouse astrocyte lipoproteins, which exhibited similar peaks but where cholesterol was predominantly non-esterified). Triglycerides were present at about 2/3 the level of cholesterol. LCAT was detected along with two of its activators, apolipoprotein (apo) A-IV and apoC-I. ApoA-I and apoA-II mRNA and protein were absent. ApoJ was present equally in all peaks but apoE was present predominantly in peaks 3 and 4. ApoB was not detected. The electron microscopic appearance of Peak 1 lipoproteins suggested partial lipolysis leading to the detection of a heparin-releasable triglyceride lipase consistent with endothelial lipase. The increased neuronal delivery of lipids from large lipoprotein particles, for which apoE4 has greater affinity than does apoE3, may be a mechanism whereby the apoE {var_epsilon}4 allele contributes to neurodegenerative risk.

  4. Adsorption of gastric lipase onto multicomponent model lipid monolayers with phase separation.

    Science.gov (United States)

    Bourlieu, Claire; Paboeuf, Gilles; Chever, Sophie; Pezennec, Stéphane; Cavalier, Jean-François; Guyomarc'h, Fanny; Deglaire, Amélie; Bouhallab, Saïd; Dupont, Didier; Carrière, Frédéric; Vié, Véronique

    2016-07-01

    The enzymatic lipolysis of complex natural lipoproteic assemblies such as milk fat globules is central in neonatal digestion. This process first requires the rapid adsorption of a lipolytic enzyme, gastric lipase, onto the membrane enveloping the triglyceride substrate before the onset of catalytic activity. The interactions governing lipase adsorption onto this complex lipid/water interface are not fully elucidated. This study was designed to unravel the interactions of recombinant dog gastric lipase (rDGL) with model monolayers presenting liquid-liquid phase coexistence and mimicking the outer leaflet of the milk fat globule membrane. Combining biophysical tools (ellipsometry, tensiometry and atomic force microscopy), it was evidenced that rDGL partitions toward liquid expanded phase and at phase boundaries. rDGL gets adsorbed at several levels of insertion suggesting molecular cooperation that may favor insertion and strongly impacts on the lipid phase lateral organization. The addition of phosphatidylserine, negatively charged, reinforced adsorption; hence besides hydrophobic interactions and as further investigated through surface potential modeling, rDGL adsorption is favored by electrostatic interactions. PMID:27011347

  5. Uremic Toxins and Lipases in Haemodialysis: A Process of Repeated Metabolic Starvation

    Directory of Open Access Journals (Sweden)

    Bernd Stegmayr

    2014-04-01

    Full Text Available Severe kidney disease results in retention of uremic toxins that inhibit key enzymes for lipid breakdown such as lipoprotein lipase (LPL and hepatic lipase (HL. For patients in haemodialysis (HD and peritoneal dialysis (PD the LPL activity is only about half of that of age and gender matched controls. Angiopoietin, like protein 3 and 4, accumulate in the uremic patients. These factors, therefore, can be considered as uremic toxins. In animal experiments it has been shown that these factors inhibit the LPL activity. To avoid clotting of the dialysis circuit during HD, anticoagulation such as heparin or low molecular weight heparin are added to the patient. Such administration will cause a prompt release of the LPL and HL from its binding sites at the endothelial surface. The liver rapidly degrades the release plasma compound of LPL and HL. This results in a lack of enzyme to degrade triglycerides during the later part of the HD and for another 3–4 h. PD patients have a similar baseline level of lipases but are not exposed to the negative effect of anticoagulation.

  6. The synthetic pentasaccharide SR 90107A/Org 31540 does not release lipase activity into the plasma.

    Science.gov (United States)

    Hoffmann, P; Bernat, A; Dumas, A; Petitou, M; Hérault, J P; Herbert, J M

    1997-05-15

    The present study was designed to find out whether the synthetic pentasaccharide SR 90107A/Org 31540, which is presently being evaluated in clinical trials as an antithrombotic agent, influences lipoprotein metabolism in rats as determined by plasma triglyceride (TG) lipase activity. A comparison with three clinically used sulphated polysaccharides-unfractionated heparin (UFH), low molecular weight heparin (LMWH) and pentosan polysulphate (PPS)- was performed. UFH evoked a dose-dependent increase in plasma TG lipase activity which plateaued at doses > or = 1 mg/kg i.v.. PPS and LMWH demonstrated a lower efficacy than heparin at 0.3 and 1 mg/kg i.v., but the maximum lipase releasing effect at 3 mg/kg i.v. was identical for UFH, PPS and LMWH. SR 90107A/Org 31540 did not release TG lipase activity at single i.v. doses up to 3 mg/kg. Repeated-dose experiments with SR 90107A/Org 31540 (1 mg/kg s.c. for 9 days) revealed no influence on the lipase releasing effect of UFH (1 mg/kg i.v. on day 10). These results demonstrate that SR 90107A/Org 31540 does not influence lipid metabolism in rats through lipase release, suggesting that SR 90107A/Org 31540 may offer an advantage over UFH and LMWH in clinical situations where an anticoagulant/antithrombotic effect is desired, but both an increase in plasma free fatty acids and atherogenic alterations of lipoprotein metabolism are considered harmful. PMID:9187020

  7. Possible role of GnIH as a mediator between adiposity and impaired testicular function

    Directory of Open Access Journals (Sweden)

    Shabana eAnjum

    2016-02-01

    Full Text Available The aim of the present study was to evaluate the roles of gonadotropin-inhibitory hormone (GnIH, as an endocrine link between increasing adiposity and impaired testicular function in mice. To achieve this, the effect of GnIH on changes in nutrients uptake and hormonal synthesis/action in the adipose tissue and testis was investigated simultaneously by in vivo study and separately by in vitro study. Mice were treated in vivo with different doses of GnIH for 8 days. In the in vitro study, adipose tissue and testes of mice were cultured with different doses of GnIH with or without insulin or LH for 24 h at 370C. The GnIH treatment in vivo showed increased food intake, up-regulation of glucose transporter 4 (GLUT4 and increased uptake of triglycerides in the adipose tissue. These changes may be responsible for increased accumulation of fat into white adipose tissue, resulted in increase in the body mass. On the contrary to the adipose tissue, treatment with GnIH both in vivo and in vitro showed decreased uptake of glucose by down-regulation of glucose transporter 8 (GLUT8 expressions in the testes, which in turn resulted in the decreased synthesis of testosterone. The GnIH treatment in vivo also showed the decreased expression of insulin receptor protein in the testis which may also be responsible for the decreased testicular activity in the mice. These findings thus suggest that GnIH increases the uptake of glucose and triglycerides in the adipose tissue resulting in increased accumulation of fat, whereas simultaneously in the testis GnIH suppressed the GLUT8 mediated glucose uptake, which in turn may be responsible for decreased testosterone synthesis. This study thus demonstrates GnIH as mediator of increasing adiposity and impaired testicular function in mice.

  8. Unreliability of triglyceride measurement to predict turbidity induced interference

    OpenAIRE

    Twomey, P J; Don-Wauchope, A C; McCullough, D

    2003-01-01

    Lipaemic specimens are a common problem in clinical chemistry. Most laboratories will measure the concentration of triglycerides and then decide whether the analytical result is valid or not. There is a poor association between the concentration of triglycerides and an objective assessment of turbidity for visually turbid specimens. Extrapolation of triglyceride concentrations derived from the use of intravenous emulsions to visually turbid specimens found in clinical practice will overestima...

  9. [Chromosomal localization of the hormone-sensitive lipase gene (Hsl) in rice field eel].

    Science.gov (United States)

    Ji, Fu-Yun; Yu, Qi-Xing; Pan, Pei-Wen

    2003-03-01

    Adipose tissue triacylglycerols are the quantitatively most important source of stored energy in animals. Hormone-sensitive lipase encoded by hormone-sensitive lipase gene (Hsl) is a multifunctional enzyme that catalyzes the hydrolysis of triacylglycerol stored in adipose tissue and cholesterol esters in the adrenals, ovaries, testes and macrophages. Using pig Hsl gene inserted into pBS labeled by the radioactive isotope and the digoxigenin as the probes respectively one band, 11.5kb, has been shown to hybridized with total DNA of rice field eel digested with Pst I by Southern blotting and Hsl gene has been assigned to metaphase chromosome 5, at the position of 78.35+/-1.26 from the centromere in rice field eel by fluorescent in situ hybridization (FISH). The mapping results are corresponding to that of "specific-chromosomal DNA pool" obtained by chromosome microisolation used to map gene and the mapping result is more accurate. The results of the study further illustrate the importance of the presence of Hsl gene in rice field eel genome and provide the first FISH mapping data for rice field eel chromosome 5. The current studies would advance the addition of known genetic markers and the construction of high resolution genetic map in rice field eel genome.

  10. The resurgence of Hormone-Sensitive Lipase (HSL) in mammalian lipolysis.

    Science.gov (United States)

    Lampidonis, Antonis D; Rogdakis, Emmanuel; Voutsinas, Gerassimos E; Stravopodis, Dimitrios J

    2011-05-15

    The ability to store energy in the form of energy-dense triacylglycerol and to mobilize these stores rapidly during periods of low carbohydrate availability or throughout the strong metabolic demand is a highly conserved process, absolutely essential for survival. In the industrialized world the regulation of this pathway is viewed as an important therapeutic target for disease prevention. Adipose tissue lipolysis is a catabolic process leading to the breakdown of triacylglycerols stored in fat cells, and release of fatty acids and glycerol. Mobilization of adipose tissue fat is mediated by the MGL, HSL and ATGL, similarly functioning enzymes. ATGL initiates lipolysis followed by the actions of HSL on diacylglycerol, and MGL on monoacylglycerol. HSL is regulated by reversible phosphorylation on five critical residues. Phosphorylation alone, however, is not enough to activate HSL. Probably, conformational alterations and a translocation from the cytoplasm to lipid droplets are also involved. In accordance, Perilipin functions as a master regulator of lipolysis, protecting or exposing the triacylglycerol core of a lipid droplet to lipases. The prototype processes of hormonal lipolytic control are the β-adrenergic stimulation and suppression by insulin, both of which affect cytoplasmic cyclic AMP levels. Lipolysis in adipocytes is an important process in the management of body energy reserves. Its deregulation may contribute to the symptoms of type 2 diabetes mellitus and other pathological situations. We, herein, discuss the metabolic regulation and function of lipases mediating mammalian lipolysis with a focus on HSL, quoting newly identified members of the lipolytic proteome.

  11. MICROBIAL LIPASES: PRODUCTION OF EXTRACELLULAR LIPASE ENZYME BY ALCALIGENES VISCOSUS (DOGE-1 STRAIN

    Directory of Open Access Journals (Sweden)

    P.Sekhar

    2012-05-01

    Full Text Available Industrially important extracellular lipase enzyme production was explored by utilizingmicrobial strain isolated from dairy effluents. Alcaligenes viscosus DOGE-1 strain isolated from dairywaste waters proved to produce extracellular lipase. Various growth factors were attempted to maximizethe lipase production by this strain. Growth factors like NH4PO4, Peptone, Urea coupled with peptone,KH2PO4, Olive oil and pH were found to be favored the maximum lipase production. This microbialstrain was found to have a high lipolytic activity.

  12. Adipose Tissue Metabolism During Hypobaria

    Directory of Open Access Journals (Sweden)

    D. P. Chattopadhyay

    1974-10-01

    Full Text Available Possible factors affecting the metabolism of adipose tissue under hypobaric conditions have been reviewed. The hormonal changes brought into play under hypoxic stress generally stress generally increase the adipose tissue lipolysis.

  13. Gene cloning and molecular characterization of the Talaromyces thermophilus lipase catalyzed efficient hydrolysis and synthesis of esters.

    Science.gov (United States)

    Romdhane, Ines Belhaj-Ben; Frikha, Fakher; Maalej-Achouri, Inès; Gargouri, Ali; Belghith, Hafedh

    2012-02-15

    A genomic bank from Talaromyces thermophilus fungus was constructed and screened using a previously isolated fragment lipase gene as probe. From several clones isolated, the nucleotide sequence of the lipase gene (TTL gene) was completed and sequenced. The TTL coding gene consists of an open reading frame (ORF) of 1083bp encoding a protein of 269 Aa with an estimated molecular mass of 30kDa. The TTL belongs to the same gene family as Thermomyces lanuginosus lipase (TLL, Lipolase®), a well known lipase with multiple applications. The promoter sequence of the TTL gene showed the conservation of known consensus sequences PacC, CreA, Hap2-3-4 and the existence of a particular sequence like the binding sites of Oleate Response Element (ORE) and Fatty acids Responsis Element (FARE) which are similar to that already found to be specific of lipolytic genes in Candida and Fusarium, respectively. Northern blot analysis showed that the TTL expression was much higher on wheat bran than on olive oil as sole carbon source. Compared to the Lipolase®, this enzyme was found to be more efficient for the hydrolysis and the synthesis of esters; and its synthetic efficiency even reached 91.6% from Waste Cooking Oil triglycerides.

  14. Impact of lipoprotein lipase gene polymorphisms on ulcerative colitis

    Institute of Scientific and Technical Information of China (English)

    Toshihito Kosaka; Taizou Shiraishi; Masatoshi Watanabe; Takayuki Yamamoto; Ai Nakahara; Takahiko Katoh; Junji Yoshino; Kazuo Inui; Takao Wakabayashi; Kazumu Okushima; Takashi Kobayashi; Hironao Miyoshi; Yuta Nakamura; Shigekazu Hayashi

    2006-01-01

    AIM: To examine the influence of lipoprotein lipase (LPL)gene polymorphism in ulcerative colitis (UC) patients.METHODS: Peripheral blood was obtained from 131 patients with UC and 106 healthy controls for DNA extraction. We determined LPL gene polymorphisms affecting the enzyme at Ser447stop, as well as Hind Ⅲ and Pvu Ⅱ polymorphisms using PCR techniques. PCR products were characterized by PCR-RFLP and direct sequencing.Polymorphisms were examined for association with clinical features in UC patients. Genotype frequencies for LPL polymorphisms were also compared between UC patients and controls.RESULTS: In patients with onset at age 20 years or younger, C/G and G/G genotypes for Ser447stop polymorphism were more prevalent than C/C genotype (OR= 3.13, 95% CI = 0.95-10.33). Patients with H+/- or H-/-genotype for HindⅢ polymorphism also were more numerous than those with H+/+ genotype (OR = 2.51, 95%CI = 0.85-7.45). In the group with H+/+ genotype for HindⅢ polymorphism, more patients had serum triglyceride concentrations over 150 mg/dL than patients with H+/- or H-/- genotype (P < 0.01, OR = 6.46, 95% CI =1.39-30.12). Hypertriglycemia was also more prevalent in patients with P+/+ genotypes for Pvu Ⅱ polymorphism (P< 0.05, OR = 3.0, 95% CI = 1.06-8.50). Genotype frequency for LPL polymorphism did not differ significantly between UC patients and controls.CONCLUSION: Ser447stop and HindⅢ LPL polymorphisms may influence age of onset of UC, while HindⅢand PvuⅡ polymorphisms influence serum triglyceride in UC patients.

  15. Diacylglycerol synthesis by enzymatic glycerolysis: Screening of commercially available lipases

    DEFF Research Database (Denmark)

    Kristensen, Janni Brogaard; Xu, X.B.; Mu, Huiling

    2005-01-01

    Seven lipases were screened for their ability to synthesize DAG in the glycerolysis of rapeseed oil. In batch reactions with free glycerol, the lipase carrier was of great importance for catalysis. Catalysis did not take place in reactions with lipases having hydrophilic carriers. The best DAG...... yield (approx. 60 wt%) was achieved with Novozym 435 and Lipase PS-D after 7 h, and an equilibrium was obtained. Stepwise addition of glycerol allowed catalysis with Novozym CALB L (immobilized) to take place in spite of the hydrophilic carrier; however, the DAG yield was only 19 wt%. This result...... suggests that glycerol forms a layer around the hydrophilic lipase particles, limiting contact between the lipases and the hydrophobic oil phase. With glycerol absorbed on silica gel, all lipases catalyzed the glycerolysis reaction. Faster conversion of TAG was obtained with Lipase PS-D, Lipase AK...

  16. [Lipases in catalytic reactions of organic chemistry].

    Science.gov (United States)

    Bezborodov, A M; Zagustina, N A

    2014-01-01

    Aspects of enzymatic catalysis in lipase-catalyzed reactions of organic synthesis are discussed in the review. The data on modern methods of protein engineering and enzyme modification allowing a broader range of used substrates are briefly summarized. The application of lipase in the preparation of pharmaceuticals and agrochemicals containing no inactive enantiomers and in the synthesis of secondary alcohol enantiomers and optically active amides is demonstrated. The subject of lipase involvement in the C-C bond formation in the Michael reaction is discussed. Data on the enzymatic synthesis of construction materials--polyesters, siloxanes, etc.--are presented. Examples demonstrating the application of lipase enzymatic catalysis in industry are given. PMID:25707112

  17. [Water binding of adsorptive immobilized lipases].

    Science.gov (United States)

    Loose, S; Meusel, D; Muschter, A; Ruthe, B

    1990-01-01

    It is supposed that not only the total water content of lipase preparations but more their state of water binding is of technological importance in enzymatic interesterification reactions in systems nearly free from water. The isotherms at 65 degrees C of two microbial lipases immobilized on various adsorbents as well as different adsorbents themselves are shown. The water binding capacity in the range of water content of technological interest decreases from the anion exchange resin Amberlyst A 21 via nonpolar adsorbent Amberlite XAD-2 to kieselguhr Celite 545. It is demonstrated that water binding by lipases is depending on temperature but is also affected by adsorptive immobilization. Adsorptive immobilized lipases show hysteresis, which is very important for preparing a definite water content of the enzyme preparations. PMID:2325750

  18. Lipase and protease extraction from activated sludge

    DEFF Research Database (Denmark)

    Gessesse, Amare; Dueholm, Thomas; Petersen, Steffen B.;

    2003-01-01

    of gentle and efficient enzyme extraction methods from environmental samples is very important. In this study we present a method for the extraction of lipases and proteases from activated sludge using the non-ionic detergent Triton X-100, EDTA, and cation exchange resin (CER), alone or in combination...... for the extraction of lipases and proteases from activated sludge. The sludge was continuously stirred in the presence of either buffer alone or in the presence of detergent and/or chelating agents. In all cases, a marked reduction in floc size was observed upon continuous stirring. However, no lipase activity...... and negligible protease activity was extracted in the presence of buffer alone, indicating that enzyme extraction was not due to shear force alone. The highest lipase activity was extracted using 0.1% Triton X-100 above which the activity was gradually decreasing. For proteases, the highest activity was obtained...

  19. Structural characterization of MAPLE deposited lipase biofilm

    International Nuclear Information System (INIS)

    Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase

  20. Structural characterization of MAPLE deposited lipase biofilm

    Energy Technology Data Exchange (ETDEWEB)

    Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Ausanio, Giovanni; Bloisi, Francesco [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Calabria, Raffaela [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Califano, Valeria, E-mail: v.califano@im.cnr.it [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Massoli, Patrizio [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Vicari, Luciano R.M. [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy)

    2014-11-30

    Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase.

  1. Dicarboxylic aciduria and medium chain triglyceride supplemented milk.

    OpenAIRE

    Henderson, M.J.; Dear, P R

    1986-01-01

    Pronounced dicarboxylic aciduria was observed in preterm infants fed a medium chain triglyceride supplemented milk formula. As many special formulas contain a medium chain triglyceride oil attention needs to be drawn to its metabolic effects, regarding the diagnosis of inborn errors of metabolism and that dicarboxylic acids might be harmful.

  2. Plasma apolipoprotein A5 and triglycerides in type 2 diabetes

    NARCIS (Netherlands)

    Dallinga-Thie, GM; Van Tol, A; Hattori, H; van Vark-van de Zee, LC; Jansen, H; Sijbrands, EJG

    2006-01-01

    Aims/hypothesis: Variation in the human apolipoprotein (APO) A5 gene (APOA5) is associated with elevated plasma triglycerides. However, data on the exact role of plasma concentrations of APOA5 in human triglyceride homeostasis are lacking. In the present study, we estimated plasma APOA5 levels in pa

  3. ANGPTL4 variants E40K and T266M are associated with lower fasting triglyceride levels in Non-Hispanic White Americans from the Look AHEAD Clinical Trial

    Directory of Open Access Journals (Sweden)

    Pownall Henry J

    2011-06-01

    Full Text Available Abstract Background Elevated triglyceride levels are a risk factor for cardiovascular disease. Angiopoietin-like protein 4 (Angptl4 is a metabolic factor that raises plasma triglyceride levels by inhibiting lipoprotein lipase (LPL. In non-diabetic individuals, the ANGPTL4 coding variant E40K has been associated with lower plasma triglyceride levels while the T266M variant has been associated with more modest effects on triglyceride metabolism. The objective of this study was to determine whether ANGPTL4 E40K and T266M are associated with triglyceride levels in the setting of obesity and T2D, and whether modification of triglyceride levels by these genetic variants is altered by a lifestyle intervention designed to treat T2D. Methods The association of ANGPTL4 E40K and T266M with fasting triglyceride levels was investigated in 2,601 participants from the Look AHEAD Clinical Trial, all of whom had T2D and were at least overweight. Further, we tested for an interaction between genotype and treatment effects on triglyceride levels. Results Among non-Hispanic White Look AHEAD participants, ANGPTL4 K40 carriers had mean triglyceride levels of 1.61 ± 0.62 mmol/L, 0.33 mmol/L lower than E40 homozygotes (p = 0.001. Individuals homozygous for the minor M266 allele (MAF 30% had triglyceride levels of 1.75 ± 0.58 mmol/L, 0.24 mmol/L lower than T266 homozygotes (p = 0.002. The association of the M266 with triglycerides remained significant even after removing K40 carriers from the analysis (p = 0.002. There was no interaction between the weight loss intervention and genotype on triglyceride levels. Conclusions This is the first study to demonstrate that the ANGPTL4 E40K and T266M variants are associated with lower triglyceride levels in the setting of T2D. In addition, our findings demonstrate that ANGPTL4 genotype status does not alter triglyceride response to a lifestyle intervention in the Look AHEAD study.

  4. LIPASES PRODUCED BY YEASTS: POWERFUL BIOCATALYSTS FOR INDUSTRIAL PURPOSES

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    Luiza Lux Lock

    2007-12-01

    Full Text Available The term “lipolytic enzymes” refers to the lipases and carboxylic ester hydrolases. Lipase production is widespread among yeasts, butfew are capable of producing lipases with interesting characteristics and in sufficient amounts to be industrially useful. The literatureconcerning lipases produced by Candida rugosa, Yarrowia (Candida lipolytica, Candida antarctica and other emerging lipaseproducingyeasts is reviewed. The use of recombinant lipases is discussed, with emphasis on the utilization of heterologous expressionsystems and design of chimeras. Finally, the three approaches that aim the improvement of lipase production or the modification of thesubstrate selectivity of the enzyme (medium engineering, biocatalyst engineering, and protein engineering are discussed.

  5. Utilization of immobilized lipases as catalysts in the transesterification of non-edible vegetable oils with ethanol

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    P. C. Tiosso

    2014-12-01

    Full Text Available This work reports the use of commercially available immobilized lipase preparations (Novozym® 435 and Lipozyme TL IM, both from Novozymes, and Lipase PS IM from Amano as catalysts in the transesterification reaction of different alkyl-chain triglycerides with ethanol. The ethanolysis of native oils from Brazilian Amazon plants andiroba (Carapa guianensis, babassu (Orbignya sp., jatropa (Jatropha curcas, and palm (Elaeis sp. was studied in a solvent-free system. In a typical reaction, the immobilized preparations were added to the mixture of vegetable oil-to-ethanol in a molar ratio of 1:9. The reactions were performed at 50 ºC for a maximum period of 48 h. Under the conditions used, all the immobilized lipase preparations were able to generate the main esters of fatty acids present in the tested feedstocks, and both the reaction rate and ester yield were dependent on the source of lipase and vegetable oil. The viscosity values for the samples obtained in each reaction displayed a consistent reduction in relation to their original feedstocks, which also confirms the high conversion of triglycerides to ethyl esters (99.8-74.0%. The best performances were obtained with Amano PS IM and Novozym® 435, with the biodiesel samples from the babassu and jatropha oils exhibiting viscosity values in accordance with those predicted by the technical standards of ASTM D6751 (1.9-6.0 mm²/s. Lipozyme TL IM displayed an unsatisfactory performance, indicating that the conditions of the transesterification reaction should be improved. This comparative study using different catalysts and several vegetable oil sources with varying fatty acid compositions is particularly important for all tropical countries with a diversity of native vegetable oil sources.

  6. Parathyroid hormone is not an inhibitor of lipoprotein lipase activity.

    Science.gov (United States)

    Arnadottir, M; Nilsson-Ehle, P

    1994-01-01

    The reduced lipoprotein lipase (LPL) activities in uraemia are reflected by increased serum triglyceride concentrations and reduced HDL cholesterol concentrations. Both hyperparathyroidism and circulating inhibitor(s) of LPL have been associated with the disturbances of lipid metabolism in uraemia. The aim of the present study was to investigate if parathyroid hormone (PTH) had an inhibitory effect on LPL activity. Plasma post-heparin LPL activities, plasma LPL inhibitory activities, serum PTHintact and serum PTHC-terminal concentrations were analysed in 20 patients on haemodialysis and 20 healthy controls. The effects of purified, human PTHintact and a carboxyterminal fragment of PTH (PTH39-84) on LPL activities in post-heparin plasma from healthy individuals and on the enzyme activity of purified, bovine milk LPL, activated with apolipoprotein CII, were studied. Patients had significantly higher plasma LPL inhibitory activities than controls, but there was no correlation between plasma LPL inhibitory activities and serum PTH concentrations. Neither PTHintact nor PTH39-84 had a significant effect on LPL activities in vitro. Thus there was no evidence of a direct inhibition of LPL activity by PTH under the present in-vivo or in-vitro conditions. PMID:7870347

  7. α-Tocopherol adipose tissue stores are depleted after burn injury in pediatric patients123

    Science.gov (United States)

    Leonard, Scott W; Traber, Daniel L; Traber, Lillian D; Gallagher, James; Bobe, Gerd; Jeschke, Marc G; Finnerty, Celeste C; Herndon, David

    2010-01-01

    Background: We previously showed that thermal injury depletes plasma vitamin E in pediatric burn patients; however, plasma changes may reflect immediate alterations in vitamin E nutriture. Adipose tissue α-tocopherol concentrations are generally accepted to reflect long-term vitamin E status. Objective: To test the hypothesis that thermal injury depletes body stores of vitamin E, α-tocopherol concentrations were measured in adipose tissue samples. Design: Pediatric patients (n = 8) were followed up to 1 y after burn injury. Surgically obtained samples were collected at various intervals and stored at −80°C in a biorepository. α- and γ-Tocopherols, cholesterol, and triglycerides were measured in the same tissue aliquot. Results: During the first week after injury, adipose tissue α-tocopherol concentrations were within the expected normal range of 199 ± 40 nmol/g adipose tissue but were substantially lower at weeks 2 and 3 (133 ± 13 and 109 ± 8 nmol/g adipose tissue, respectively). Individual rates of decrease, estimated by linear regression, showed that adipose tissue α-tocopherol decreased by an average of 6.1 ± 0.6 nmol/g daily. During the first month after injury, adipose tissue triglyceride concentrations also decreased, whereas no changes in cholesterol concentrations occurred. Conclusions: These data emphasize that the burn injury experienced by these pediatric patients altered their metabolism such that vitamin E status diminished during the month after injury. Further studies are needed to evaluate the mechanism and consequences of the observed vitamin E depletion. This trial was registered at clinicaltrials.gov as NCT00675714. PMID:20881067

  8. Subcutaneous adipose tissue classification

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    A. Sbarbati

    2010-11-01

    Full Text Available The developments in the technologies based on the use of autologous adipose tissue attracted attention to minor depots as possible sampling areas. Some of those depots have never been studied in detail. The present study was performed on subcutaneous adipose depots sampled in different areas with the aim of explaining their morphology, particularly as far as regards stem niches. The results demonstrated that three different types of white adipose tissue (WAT can be differentiated on the basis of structural and ultrastructural features: deposit WAT (dWAT, structural WAT (sWAT and fibrous WAT (fWAT. dWAT can be found essentially in large fatty depots in the abdominal area (periumbilical. In the dWAT, cells are tightly packed and linked by a weak net of isolated collagen fibers. Collagenic components are very poor, cells are large and few blood vessels are present. The deep portion appears more fibrous then the superficial one. The microcirculation is formed by thin walled capillaries with rare stem niches. Reinforcement pericyte elements are rarely evident. The sWAT is more stromal; it is located in some areas in the limbs and in the hips. The stroma is fairly well represented, with a good vascularity and adequate staminality. Cells are wrapped by a basket of collagen fibers. The fatty depots of the knees and of the trochanteric areas have quite loose meshes. The fWAT has a noteworthy fibrous component and can be found in areas where a severe mechanic stress occurs. Adipocytes have an individual thick fibrous shell. In conclusion, the present study demonstrates evident differences among subcutaneous WAT deposits, thus suggesting that in regenerative procedures based on autologous adipose tissues the sampling area should not be randomly chosen, but it should be oriented by evidence based evaluations. The structural peculiarities of the sWAT, and particularly of its microcirculation, suggest that it could represent a privileged source for

  9. Chylous ascites secondary to hyperlipidemic pancreatitis with normal serum amylase and lipase

    Institute of Scientific and Technical Information of China (English)

    Fahmi Yousef Khan; Tssa Matar

    2007-01-01

    A 54-year old man with a family history of hyperlipidemia was admitted with a 12 h history of severe generalized abdominal pain associated with nausea, vomiting and abdominal distension. Examination of the abdomen revealed tenderness in the periumblical area with shifting dullness. Serum pancreatic amylase was 29 IU/L and lipase 44 IU/L, triglyceride 36.28 mmol/L. Ultrasound showed ascites. CT of the abdomen with contrast showed inflammatory changes surrounding the pancreas consistent with acute pancreatitis. Ultrasound (US)guided abdomen paracentesis yielded a milky fluid with high triglyceride content consistent with chylous ascites.The patient was kept fasting and intravenous fluid hydration was provided. Meperidine was administered for pain relief. On the following days the patient's condition improved and he was gradually restarted on a low-fat diet, and fat lowering agent (gemfibrozil) was begun,600 mg twice a day. On d 14, abdomen US was repeated and showed fluid free peritoneal cavity. The patient was discharged after 18 d of hospitalization with 600 mg gemfibrozil twice a day. At the time of discharge, the fasting triglyceride was 4.2 mmol/L. After four weeks the patient was seen in the clinic, he was well.

  10. Application of a Burkholderia cepacia lipase-immobilized silica monolith to batch and continuous biodiesel production with a stoichiometric mixture of methanol and crude Jatropha oil

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    Takahashi Ryo

    2011-10-01

    Full Text Available Abstract Background The enzymatic production of biodiesel through alcoholysis of triglycerides has become more attractive because it shows potential in overcoming the drawbacks of chemical processes. In this study, we investigate the production of biodiesel from crude, non-edible Jatropha oil and methanol to characterize Burkholderia cepacia lipase immobilized in an n-butyl-substituted hydrophobic silica monolith. We also evaluate the performance of a lipase-immobilized silica monolith bioreactor in the continuous production of biodiesel. Results The Jatropha oil used contained 18% free fatty acids, which is problematic in a base-catalyzed process. In the lipase-catalyzed reaction, the presence of free fatty acids made the reaction mixture homogeneous and allowed bioconversion to proceed to 90% biodiesel yield after a 12 hour reaction time. The optimal molar ratio of methanol to oil was 3.3 to 3.5 parts methanol to one part oil, with water content of 0.6% (w/w. Further experiments revealed that B. cepacia lipase immobilized in hydrophobic silicates was sufficiently tolerant to methanol, and glycerol adsorbed on the support disturbed the reaction to some extent in the present reaction system. The continuous production of biodiesel was performed at steady state using a lipase-immobilized silica monolith bioreactor loaded with 1.67 g of lipase. The yield of 95% was reached at a flow rate of 0.6 mL/h, although the performance of the continuous bioreactor was somewhat below that predicted from the batch reactor. The bioreactor was operated successfully for almost 50 days with 80% retention of the initial yield. Conclusions The presence of free fatty acids originally contained in Jatropha oil improved the reaction efficiency of the biodiesel production. A combination of B. cepacia lipase and its immobilization support, n-butyl-substituted silica monolith, was effective in the production of biodiesel. This procedure is easily applicable to the design

  11. Triacylglycerol kinetics in endotoxic rats with suppressed lipoprotein lipase activity

    Energy Technology Data Exchange (ETDEWEB)

    Bagby, G.J.; Corll, C.B.; Martinez, R.R.

    1987-07-01

    Hypertriglyceridemia observed in animals after bacterial endotoxin administration and some forms of sepsis can result from increased hepatic triacylglycerol (TG) output or decreased TG clearance by extrahepatic tissues. To differentiate between these two possibilities, TG and free fatty acid (FFA) kinetics were determined in control and endotoxin-injected rats 18 h after treatment. Plasma TG and FFA kinetics were assessed by a constant intravenous infusion with (9,10-/sup 3/H)palmitate-labeled very low-density lipoprotein and (1-/sup 14/C)palmitate bound to albumin, respectively. In addition, lipoprotein lipase (LPL) activity was determined in heart, skeletal muscle, and adipose tissue as well as in postheparin plasma of functionally hepatectomized, adrenalectomized, and gonadectomized rats. Plasma FFA acid concentrations were slightly increased in endotoxin-treated rats but their turnover did not differ from control. Endotoxin-treated rats had a threefold increase in plasma TG concentrations and decreased heart, skeletal muscle, and post-heparin plasma LPL activity. Plasma TG turnover was decreased, indicating that hypertriglyceridemia was not due to an increased TG output by the liver. Instead, the endotoxin-induced increase in plasma TG concentration was consequence of the 80% reduction in TG metabolic clearance rate. Thus, suppression of LPL activity in endotoxic animals impairs TG clearance resulting in hypertriglyceridemia. Furthermore, endotoxin administration reduced the delivery of TG-FFA to extrahepatic tissues because hepatic synthesis and secretion of TG from plasma FFA was decreased and LPL activity was suppressed.

  12. Transcriptional regulation of adipocyte hormone-sensitive lipase by glucose.

    Science.gov (United States)

    Smih, Fatima; Rouet, Philippe; Lucas, Stéphanie; Mairal, Aline; Sengenes, Coralie; Lafontan, Max; Vaulont, Sophie; Casado, Marta; Langin, Dominique

    2002-02-01

    Hormone-sensitive lipase (HSL) catalyzes the rate-limiting step in the mobilization of fatty acids from adipose tissue, thus determining the supply of energy substrates in the body. HSL mRNA was positively regulated by glucose in human adipocytes. Pools of stably transfected 3T3-F442A adipocytes were generated with human adipocyte HSL promoter fragments from -2,400/+38 to -31/+38 bp linked to the luciferase gene. A glucose-responsive region was mapped within the proximal promoter (-137 bp). Electromobility shift assays showed that upstream stimulatory factor (USF)-1 and USF2 and Sp1 and Sp3 bound to a consensus E-box and two GC-boxes in the -137-bp region. Cotransfection of the -137/+38 construct with USF1 and USF2 expression vectors produced enhanced luciferase activity. Moreover, HSL mRNA levels were decreased in USF1- and USF2-deficient mice. Site-directed mutagenesis of the HSL promoter showed that the GC-boxes, although contributing to basal promoter activity, were dispensable for glucose responsiveness. Mutation of the E-box led to decreased promoter activity and suppression of the glucose response. Analogs and metabolites were used to determine the signal metabolite of the glucose response. The signal is generated downstream of glucose-6-phosphate in the glycolytic pathway before the triose phosphate step. PMID:11812735

  13. Comparison of serum triglyceride levels with propofol in long chain triglyceride and propofol in medium and long chain triglyceride after short term anesthesia in pediatric patients

    Directory of Open Access Journals (Sweden)

    Ishwar Bhukal

    2014-01-01

    Full Text Available Background: Significant increase in serum triglyceride (ST concentration have been described in adult population after prolonged administration of propofol formulation containing long chain triglyceride (LCT. Though, medium chain triglyceride-LCT (MCT-LCT propofol when compared with LCT propofol for long-term sedation in adults resulted in identical triglyceride levels, the elimination of triglyceride was faster in patients administered MCT-LCT propofol. Materials and Methods: A total of 40 children were randomized into two groups of 20 each; Group I were induced with 1% LCT propofol (3 mg/kg and Group II with 1% medium and LCT propofol and maintained with descalating dose of 20.15 and 10 mg/kg/h at 10 min intervals. Blood samples for ST concentration were obtained before induction of anesthesia, at the end of propofol infusion and 4 h after terminating propofol infusion. Results: ST levels were raised significantly above the basal values in both the groups but the rise was significantly higher in Group I (P < 0.05. Four hours after stopping propofol infusion the triglyceride levels were similar to the basal values in Group II, whereas in Group I the values were significantly greater than the baseline (P < 0.05 as well as those of Group II (P < 0.05. No clinically significant adverse effect of hypertriglyceridemia was observed. Conclusion: Even short term anesthesia with LCT and MCT-LCT propofol (1% leads to elevated ST levels. The increase in ST levels is less with MCT-LCT propofol and elimination of triglyceride is also rapid after terminating MCT-LCT propofol infusion.

  14. Cardiac expression of microsomal triglyceride transfer protein is increased in obesity and serves to attenuate cardiac triglyceride accumulation.

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    Emil D Bartels

    Full Text Available Obesity causes lipid accumulation in the heart and may lead to lipotoxic heart disease. Traditionally, the size of the cardiac triglyceride pool is thought to reflect the balance between uptake and beta-oxidation of fatty acids. However, triglycerides can also be exported from cardiomyocytes via secretion of apolipoproteinB-containing (apoB lipoproteins. Lipoprotein formation depends on expression of microsomal triglyceride transfer protein (MTP; the mouse expresses two isoforms of MTP, A and B. Since many aspects of the link between obesity-induced cardiac disease and cardiac lipid metabolism remain unknown, we investigated how cardiac lipoprotein synthesis affects cardiac expression of triglyceride metabolism-controlling genes, insulin sensitivity, and function in obese mice. Heart-specific ablation of MTP-A in mice using Cre-loxP technology impaired upregulation of MTP expression in response to increased fatty acid availability during fasting and fat feeding. This resulted in cardiac triglyceride accumulation but unaffected cardiac insulin-stimulated glucose uptake. Long-term fat-feeding of male C57Bl/6 mice increased cardiac triglycerides, induced cardiac expression of triglyceride metabolism-controlling genes and attenuated heart function. Abolishing cardiac triglyceride accumulation in fat-fed mice by overexpression of an apoB transgene in the heart prevented the induction of triglyceride metabolism-controlling genes and improved heart function. The results suggest that in obesity, the physiological increase of cardiac MTP expression serves to attenuate cardiac triglyceride accumulation albeit without major effects on cardiac insulin sensitivity. Nevertheless, the data suggest that genetically increased lipoprotein secretion prevents development of obesity-induced lipotoxic heart disease.

  15. Lipidomic Profiling of Adipose Tissue Reveals an Inflammatory Signature in Cancer-Related and Primary Lymphedema

    OpenAIRE

    Sedger, Lisa M.; Tull, Dedreia L.; Malcolm J McConville; De Souza, David P.; Rupasinghe, Thusitha W. T.; Williams, Spencer J; Saravanan Dayalan; Daniel Lanzer; Helen Mackie; Lam, Thomas C.; John Boyages

    2016-01-01

    Cancer-related and primary lymphedema (LE) are associated with the production of adipose tissue (AT). Nothing is known, however, about the lipid-based molecules that comprise LE AT. We therefore analyzed lipid molecules in lipoaspirates and serum obtained from LE patients, and compared them to lipoaspirates from cosmetic surgery patients and healthy control cohort serum. LE patient serum analysis demonstrated that triglycerides, HDL- and LDL-cholesterol and lipid transport molecules remained ...

  16. Adipose Tissue Fatty Acid Storage Factors: Effects of Depot, Sex and Fat Cell Size

    OpenAIRE

    Hames, Kazanna C.; Koutsari, Christina; Santosa, Sylvia; Bush, Nikki C.; Jensen, Michael D.

    2015-01-01

    Background/Objectives Patterns of postabsorptive adipose tissue fatty acid storage correlate with sex-specific body fat distribution. Some proteins and enzymes participating in this pathway include CD36 (facilitated transport), acyl-CoA synthetases (ACS; the first step in fat metabolism), and diacylglycerol acetyl-transferase (DGAT; the final step of triglyceride synthesis). Our goal was to better define CD36, ACS and DGAT in relation to sex, subcutaneous fat depots, and adipocyte size. Subje...

  17. Independent Stem Cell Lineages Regulate Adipose Organogenesis and Adipose Homeostasis

    Directory of Open Access Journals (Sweden)

    Yuwei Jiang

    2014-11-01

    Full Text Available Adipose tissues have striking plasticity, highlighted by childhood and adult obesity. Using adipose lineage analyses, smooth muscle actin (SMA-mural cell-fate mapping, and conditional PPARγ deletion to block adipocyte differentiation, we find two phases of adipocyte generation that emanate from two independent adipose progenitor compartments: developmental and adult. These two compartments are sequentially required for organ formation and maintenance. Although both developmental and adult progenitors are specified during the developmental period and express PPARγ, they have distinct microanatomical, functional, morphogenetic, and molecular profiles. Furthermore, the two compartments derive from different lineages; whereas adult adipose progenitors fate-map from an SMA+ mural lineage, developmental progenitors do not. Remarkably, the adult progenitor compartment appears to be specified earlier than the developmental cells and then enters the already developmentally formed adipose depots. Thus, two distinct cell compartments control adipose organ development and organ homeostasis, which may provide a discrete therapeutic target for childhood and adult obesity.

  18. Isolated co-lipase deficiency in two brothers.

    OpenAIRE

    Hildebrand, H; Borgström, B.; Békássy, A; Erlanson-Albertsson, C; Helin, I

    1982-01-01

    Two normally developed Assyrian brothers with isolated pancreatic co-lipase deficiency are described. They presented at the age of 5-6 years with loose stools. They had steatorrhoea, and analysis of exocrine pancreatic enzymes in the small intestine showed co-lipase deficiency, while amylase, chymotrypsin, trypsin and lipase were normal. Intraduodenal infusion of purified co-lipase improved fat digestion measured by the triolein breath test. Their steatorrhoea diminished on treatment with ent...

  19. Efficient biocatalyst by encapsulating lipase into nanoporous gold

    OpenAIRE

    Du, Xiaoyu; Liu, Xueying; Li, Yufei; Wu, Chao; Wang, Xia; Xu, Ping

    2013-01-01

    Lipases are one of the most important biocatalysts for biotechnological applications. Immobilization is an efficient method to increase the stability and reusability of lipases. In this study, nanoporous gold (NPG), a new kind of nanoporous material with tunable porosity and excellent biocompatibility, was employed as an effective support for lipase immobilization. The pore size of NPG and adsorption time played key roles in the construction of lipase-NPG biocomposites. The morphology and com...

  20. Unreliability of triglyceride measurement to predict turbidity induced interference.

    Science.gov (United States)

    Twomey, P J; Don-Wauchope, A C; McCullough, D

    2003-11-01

    Lipaemic specimens are a common problem in clinical chemistry. Most laboratories will measure the concentration of triglycerides and then decide whether the analytical result is valid or not. There is a poor association between the concentration of triglycerides and an objective assessment of turbidity for visually turbid specimens. Extrapolation of triglyceride concentrations derived from the use of intravenous emulsions to visually turbid specimens found in clinical practice will overestimate the turbidity induced interference in assays (non-turbid interferences are probably the same). The evaluation of turbidity induced interference needs to be standardised using objective assessments of turbidity.

  1. ApoC-III inhibits clearance of triglyceride-rich lipoproteins through LDL family receptors.

    Science.gov (United States)

    Gordts, Philip L S M; Nock, Ryan; Son, Ni-Huiping; Ramms, Bastian; Lew, Irene; Gonzales, Jon C; Thacker, Bryan E; Basu, Debapriya; Lee, Richard G; Mullick, Adam E; Graham, Mark J; Goldberg, Ira J; Crooke, Rosanne M; Witztum, Joseph L; Esko, Jeffrey D

    2016-08-01

    Hypertriglyceridemia is an independent risk factor for cardiovascular disease, and plasma triglycerides (TGs) correlate strongly with plasma apolipoprotein C-III (ApoC-III) levels. Antisense oligonucleotides (ASOs) for ApoC-III reduce plasma TGs in primates and mice, but the underlying mechanism of action remains controversial. We determined that a murine-specific ApoC-III-targeting ASO reduces fasting TG levels through a mechanism that is dependent on low-density lipoprotein receptors (LDLRs) and LDLR-related protein 1 (LRP1). ApoC-III ASO treatment lowered plasma TGs in mice lacking lipoprotein lipase (LPL), hepatic heparan sulfate proteoglycan (HSPG) receptors, LDLR, or LRP1 and in animals with combined deletion of the genes encoding HSPG receptors and LDLRs or LRP1. However, the ApoC-III ASO did not lower TG levels in mice lacking both LDLR and LRP1. LDLR and LRP1 were also required for ApoC-III ASO-induced reduction of plasma TGs in mice fed a high-fat diet, in postprandial clearance studies, and when ApoC-III-rich or ApoC-III-depleted lipoproteins were injected into mice. ASO reduction of ApoC-III had no effect on VLDL secretion, heparin-induced TG reduction, or uptake of lipids into heart and skeletal muscle. Our data indicate that ApoC-III inhibits turnover of TG-rich lipoproteins primarily through a hepatic clearance mechanism mediated by the LDLR/LRP1 axis. PMID:27400128

  2. Impact of Doxorubicin Treatment on the Physiological Functions of White Adipose Tissue.

    Directory of Open Access Journals (Sweden)

    Luana Amorim Biondo

    Full Text Available White adipose tissue (WAT plays a fundamental role in maintaining energy balance and important endocrine functions. The loss of WAT modifies adipokine secretion and disrupts homeostasis, potentially leading to severe metabolic effects and a reduced quality of life. Doxorubicin is a chemotherapeutic agent used clinically because of its good effectiveness against various types of cancer. However, doxorubicin has deleterious effects in many healthy tissues, including WAT, liver, and skeletal and cardiac muscles. Our objective was to investigate the effects of doxorubicin on white adipocytes through in vivo and in vitro experiments. Doxorubicin reduced the uptake of glucose by retroperitoneal adipocytes and 3T3-L1 cells via the inhibition of AMP-activated protein kinase Thr172 phosphorylation and glucose transporter 4 content. Doxorubicin also reduced the serum level of adiponectin and, to a greater extent, the expression of genes encoding lipogenic (Fas and Acc and adipogenic factors (Pparg, C/ebpa, and Srebp1c in retroperitoneal adipose tissue. In addition, doxorubicin inhibited both lipogenesis and lipolysis and reduced the hormone-sensitive lipase and adipose tissue triacylglycerol lipase protein levels. Therefore, our results demonstrate the impact of doxorubicin on WAT. These results are important to understand some side effects observed in patients receiving chemotherapy and should encourage new adjuvant treatments that aim to inhibit these side effects.

  3. The regulation of HSL and LPL expression by DHT and flutamide in human subcutaneous adipose tissue.

    Science.gov (United States)

    Anderson, L A; McTernan, P G; Harte, A L; Barnett, A H; Kumar, S

    2002-05-01

    Clinical observations suggest a role for testosterone in the accumulation of central adiposity and with an associated increased risk of disease. To date, no human study has analysed the role of dihydrotestosterone (DHT) on adipose tissue mass regulation in vitro. This study investigated the role of DHT and androgen receptors (AR) in the regulation of lipolysis and lipogenesis by examining the key enzymes hormone sensitive lipase (HSL) and lipoprotein lipase (LPL) respectively. Isolated abdominal subcutaneous adipocytes (Scad) (n = 15) were treated with either DHT (10(-7)-10(-9) m), an antiandrogen, flutamide (FLT: 10(-7)-10(-9) m) or a combination of DHT (10(-7)-10(-9) m) with FLT (10(-8) m). Relative protein expression of HSL, LPL and AR was determined. In Scad, DHT inhibited HSL expression maximally at 10(-9) m (0.7 +/- 0.4**; p HSL expression data. LPL expression was reduced at all doses with combinations of DHT + FLT compared with DHT alone. Androgen receptor expression studies showed an inverse correlation with DHT, whereas DHT + FLT reduced AR expression. These studies indicate that DHT may alter HSL and LPL expression, whereas only LPL expression appears mediated by AR. These findings suggest a physiological role for DHT in the control of adipose tissue mass in women, and indicate that androgens may also play an important role in regulating lipid metabolism.

  4. Impact of Doxorubicin Treatment on the Physiological Functions of White Adipose Tissue.

    Science.gov (United States)

    Biondo, Luana Amorim; Lima Junior, Edson Alves; Souza, Camila Oliveira; Cruz, Maysa Mariana; Cunha, Roberta D C; Alonso-Vale, Maria Isabel; Oyama, Lila Missae; Nascimento, Claudia M Oller; Pimentel, Gustavo Duarte; Dos Santos, Ronaldo V T; Lira, Fabio Santos; Rosa Neto, José Cesar

    2016-01-01

    White adipose tissue (WAT) plays a fundamental role in maintaining energy balance and important endocrine functions. The loss of WAT modifies adipokine secretion and disrupts homeostasis, potentially leading to severe metabolic effects and a reduced quality of life. Doxorubicin is a chemotherapeutic agent used clinically because of its good effectiveness against various types of cancer. However, doxorubicin has deleterious effects in many healthy tissues, including WAT, liver, and skeletal and cardiac muscles. Our objective was to investigate the effects of doxorubicin on white adipocytes through in vivo and in vitro experiments. Doxorubicin reduced the uptake of glucose by retroperitoneal adipocytes and 3T3-L1 cells via the inhibition of AMP-activated protein kinase Thr172 phosphorylation and glucose transporter 4 content. Doxorubicin also reduced the serum level of adiponectin and, to a greater extent, the expression of genes encoding lipogenic (Fas and Acc) and adipogenic factors (Pparg, C/ebpa, and Srebp1c) in retroperitoneal adipose tissue. In addition, doxorubicin inhibited both lipogenesis and lipolysis and reduced the hormone-sensitive lipase and adipose tissue triacylglycerol lipase protein levels. Therefore, our results demonstrate the impact of doxorubicin on WAT. These results are important to understand some side effects observed in patients receiving chemotherapy and should encourage new adjuvant treatments that aim to inhibit these side effects.

  5. Impact of Doxorubicin Treatment on the Physiological Functions of White Adipose Tissue

    Science.gov (United States)

    Cruz, Maysa Mariana; Cunha, Roberta D. C.; Alonso-Vale, Maria Isabel; Oyama, Lila Missae; Nascimento, Claudia M. Oller; Pimentel, Gustavo Duarte; dos Santos, Ronaldo V. T.; Lira, Fabio Santos

    2016-01-01

    White adipose tissue (WAT) plays a fundamental role in maintaining energy balance and important endocrine functions. The loss of WAT modifies adipokine secretion and disrupts homeostasis, potentially leading to severe metabolic effects and a reduced quality of life. Doxorubicin is a chemotherapeutic agent used clinically because of its good effectiveness against various types of cancer. However, doxorubicin has deleterious effects in many healthy tissues, including WAT, liver, and skeletal and cardiac muscles. Our objective was to investigate the effects of doxorubicin on white adipocytes through in vivo and in vitro experiments. Doxorubicin reduced the uptake of glucose by retroperitoneal adipocytes and 3T3-L1 cells via the inhibition of AMP-activated protein kinase Thr172 phosphorylation and glucose transporter 4 content. Doxorubicin also reduced the serum level of adiponectin and, to a greater extent, the expression of genes encoding lipogenic (Fas and Acc) and adipogenic factors (Pparg, C/ebpa, and Srebp1c) in retroperitoneal adipose tissue. In addition, doxorubicin inhibited both lipogenesis and lipolysis and reduced the hormone-sensitive lipase and adipose tissue triacylglycerol lipase protein levels. Therefore, our results demonstrate the impact of doxorubicin on WAT. These results are important to understand some side effects observed in patients receiving chemotherapy and should encourage new adjuvant treatments that aim to inhibit these side effects. PMID:27015538

  6. Lipoprotein lipase: size of the functional unit determined by radiation inactivation

    International Nuclear Information System (INIS)

    Radiation inactivation was used to determine the functional molecular weight of lipoprotein lipase (LPL) in rat heart and adipose tissues. This technique reveals the size of the smallest unit required to carry out the enzyme function. Supernatant fractions of the tissue homogenates were exposed to high energy electrons at -135 degrees C. LPL activity showed a simple exponential decay in all samples tested. Because changes in nutritional state shift the distribution of LPL between the capillary endothelial and parenchymal cells within heart and adipose tissues, fasted and refed rats were used for the radiation studies. The functional molecular weight was calculated to be 127,000 +/- 15,000 (mean +/- SD) daltons for heart and adipose. Thus, the smallest unit required for enzyme function was the same in both of these tissues and did not vary with nutritional state. The data suggest that, compared with LPL monomer sizes reported in the range 55,000 to 72,000, this active unit constitutes a dimer

  7. Expression of Resistin Protein in Normal Human Subcutaneous Adipose Tissue and Pregnant Women Subcutaneous Adipose Tissue and Placenta

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yongming; GUO Tiecheng; ZHANG Muxun; GUO Wei; YU Meixia; XUE Keying; HUANG Shiang; CHEN Yanhong; ZHU Huanli; XU Lijun

    2006-01-01

    The expression of resistin protein in normal human abdominal, thigh, pregnant women abdominal, non-pregnant women abdominal subcutaneous adipose tissue and placenta and the relationship between obesity, type 2 diabetes mellitus (T2DM), pregnant physiological insulin resistance (IR) and gestational diabetes mellitus (GDM) was investigated. The expression of resistin protein in normal human abdominal, thigh, pregnant women abdominal, non-pregnant women abdominal subcutaneous adipose tissue and placenta was detected by using Western blotting method.Fasting serum glucose concentration was measured by glucose oxidase assay. Serum cholesterol (CHOL), serum triglycerides (TG), serum HDL cholesterol (HDL-C) and serum LDL cholesterol (LDL-C) were determined by full automatic biochemical instrument. Fasting insulin was measured by enzyme immunoassay to calculate insulin resistance index (IRI). Height, weight, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured to calculate body mass index (BMI) and body fat percentage (BF %). Resistin protein expression in pregnant women placental tissue (67 905±8441) (arbitrary A values) was much higher than that in subcutaneous adipose tissue in pregnant women abdomen (40 718 ± 3818, P < 0.01), non-pregnant women abdomen (38 288±2084, P<0.01), normal human abdomen (39 421±6087, P<0.01)and thigh (14 942 ±6706, P<0. 001) respectively. The resistin expression in abdominal subcutaneous adipose tissue showed no significant difference among pregnant, non-pregnant women and normal human, but much higher than that in thigh subcutaneous adipose tissue (P<0. 001). Pearson analysis revealed that resistin protein was correlated with BMI (r=0.42), fasting insulin concentration (r=0.38),IRI (r=0. 34), BF % (r=0.43) and fasting glucose (r=0. 39), but not with blood pressure,CHOL, TG, HDL-C and LDL-C. It was suggested that resistin protein expression in human abdominal subcutaneous adipose tissue was much higher

  8. Lipase production by diverse phylogenetic clades of Aureobasidium pullulans

    Science.gov (United States)

    Thirty-nine strains representing 12 diverse phylogenetic clades of Aureobasidium pullulans were surveyed for lipase production using a quantitative assay. Strains in clades 4 and 10 produced 0.2-0.3 U lipase/ml, while color variant strain NRRL Y-2311-1 in clade 8 produced 0.54 U lipase/ml. Strains i...

  9. Adipose tissue extract promotes adipose tissue regeneration in an adipose tissue engineering chamber model.

    Science.gov (United States)

    Lu, Zijing; Yuan, Yi; Gao, Jianhua; Lu, Feng

    2016-05-01

    An adipose tissue engineering chamber model of spontaneous adipose tissue generation from an existing fat flap has been described. However, the chamber does not completely fill with adipose tissue in this model. Here, the effect of adipose tissue extract (ATE) on adipose tissue regeneration was investigated. In vitro, the adipogenic and angiogenic capacities of ATE were evaluated using Oil Red O and tube formation assays on adipose-derived stem cells (ASCs) and rat aortic endothelial cells (RAECs), respectively. In vivo, saline or ATE was injected into the adipose tissue engineering chamber 1 week after its implantation. At different time points post-injection, the contents were morphometrically, histologically, and immunohistochemically evaluated, and the expression of growth factors and adipogenic genes was analyzed by enzyme-linked immunosorbent assay (ELISA) and quantitative real-time PCR. With the exception of the baseline control group, in which fat flaps were not inserted into a chamber, the total volume of fat flap tissue increased significantly in all groups, especially in the ATE group. Better morphology and structure, a thinner capsule, and more vessels were observed in the ATE group than in the control group. Expression of angiogenic growth factors and adipogenic markers were significantly higher in the ATE group. ATE therefore significantly promoted adipose tissue regeneration and reduced capsule formation in an adipose tissue engineering chamber model. These data suggest that ATE provides a more angiogenic and adipogenic microenvironment for adipose tissue formation by releasing various cytokines and growth factors that also inhibit capsule formation.

  10. Steroid biosynthesis in adipose tissue.

    Science.gov (United States)

    Li, Jiehan; Papadopoulos, Vassilios; Vihma, Veera

    2015-11-01

    Tissue-specific expression of steroidogenic enzymes allows the modulation of active steroid levels in a local manner. Thus, the measurement of local steroid concentrations, rather than the circulating levels, has been recognized as a more accurate indicator of the steroid action within a specific tissue. Adipose tissue, one of the largest endocrine tissues in the human body, has been established as an important site for steroid storage and metabolism. Locally produced steroids, through the enzymatic conversion from steroid precursors delivered to adipose tissue, have been proven to either functionally regulate adipose tissue metabolism, or quantitatively contribute to the whole body's steroid levels. Most recently, it has been suggested that adipose tissue may contain the steroidogenic machinery necessary for the initiation of steroid biosynthesis de novo from cholesterol. This review summarizes the evidence indicating the presence of the entire steroidogenic apparatus in adipose tissue and discusses the potential roles of local steroid products in modulating adipose tissue activity and other metabolic parameters.

  11. Relationship of adipocyte size with adiposity and metabolic risk factors in Asian Indians.

    Directory of Open Access Journals (Sweden)

    Ved Prakash Meena

    Full Text Available Enlargement of adipocyte is associated with their dysfunction and alterations in metabolic functions.We evaluated the association of adipocyte size of subcutaneous and omental adipose tissue with body composition and cardiovascular risk factors in Asian Indians.Eighty (40 males and 40 females non-diabetic adult subjects undergoing elective abdominal surgery were included. Pre-surgery evaluation included anthropometric measurements, % body fat by bioimpedance, abdominal fat area at L2-3 level (computed tomography and biochemical investigations (fasting blood glucose and insulin, lipids and hsCRP. During surgery, about 5 grams each of omental and subcutaneous adipose tissue was obtained for adipocyte size determination.Females had higher BMI, % body fat, skinfold thickness, total and subcutaneous abdominal fat area as compared to males. Overweight was present in 42.5% and 67.5%, and abdominal obesity in 5% and 52.5% males and females, respectively. Subcutaneous adipocyte size was significantly higher than omental adipocyte size. Omental adipocyte size correlated more strongly than subcutaneous adipocyte size with measures of adiposity (BMI, waist circumference, %BF, total and subcutaneous abdominal fat area and biochemical measures (fasting glucose, total cholesterol, triglycerides and HOMA-IR, the correlations being stronger in females. The correlation of adipocyte size with metabolic parameters was attenuated after adjusting for measures of adiposity.Omental adipocyte size, though smaller than the subcutaneous adipocyte size, was more closely related to measures of adiposity and metabolic parameters. However, the relationship was not independent of measures of adiposity.

  12. Overexpression of Rad in muscle worsens diet-induced insulin resistance and glucose intolerance and lowers plasma triglyceride level

    Science.gov (United States)

    Ilany, Jacob; Bilan, Philip J.; Kapur, Sonia; Caldwell, James S.; Patti, Mary-Elizabeth; Marette, Andre; Kahn, C. Ronald

    2006-03-01

    Rad is a low molecular weight GTPase that is overexpressed in skeletal muscle of some patients with type 2 diabetes mellitus and/or obesity. Overexpression of Rad in adipocytes and muscle cells in culture results in diminished insulin-stimulated glucose uptake. To further elucidate the potential role of Rad in vivo, we have generated transgenic (tg) mice that overexpress Rad in muscle using the muscle creatine kinase (MCK) promoter-enhancer. Rad tg mice have a 6- to 12-fold increase in Rad expression in muscle as compared to wild-type littermates. Rad tg mice grow normally and have normal glucose tolerance and insulin sensitivity, but have reduced plasma triglyceride levels. On a high-fat diet, Rad tg mice develop more severe glucose intolerance than the wild-type mice; this is due to increased insulin resistance in muscle, as exemplified by a rightward shift in the dose-response curve for insulin stimulated 2-deoxyglucose uptake. There is also a unexpected further reduction of the plasma triglyceride levels that is associated with increased levels of lipoprotein lipase in the Rad tg mice. These results demonstrate a potential synergistic interaction between increased expression of Rad and high-fat diet in creation of insulin resistance and altered lipid metabolism present in type 2 diabetes. diabetes mellitus | glucose transport | RGK GTPase | transgenic mouse

  13. Triglyceride-Rich Lipoproteins and Atherosclerotic Cardiovascular Disease

    DEFF Research Database (Denmark)

    Nordestgaard, Børge G

    2016-01-01

    Scientific interest in triglyceride-rich lipoproteins has fluctuated over the past many years, ranging from beliefs that these lipoproteins cause atherosclerotic cardiovascular disease (ASCVD) to being innocent bystanders. Correspondingly, clinical recommendations have fluctuated from a need...... to reduce levels to no advice on treatment. New insight in epidemiology now suggests that these lipoproteins, marked by high triglycerides, are strong and independent predictors of ASCVD and all-cause mortality, and that their cholesterol content or remnant cholesterol likewise are strong predictors...... of ASCVD. Of all adults, 27% have triglycerides >2 mmol/L (176 mg/dL), and 21% have remnant cholesterol >1 mmol/L (39 mg/dL). For individuals in the general population with nonfasting triglycerides of 6.6 mmol/L (580 mg/dL) compared with individuals with levels of 0.8 mmol/L (70 mg/dL), the risks were 5...

  14. Lipoprotein lipase and endothelial lipase in human testis and in germ cell neoplasms

    DEFF Research Database (Denmark)

    Nielsen, J E; Lindegaard, M L; Friis-Hansen, L;

    2009-01-01

    The aim of this study was to investigate endothelial lipase (EL, LIPG) and lipoprotein lipase (LPL) mRNA and protein expression in normal human testis and testicular germ cell tumours (GCT). Both EL and LPL were expressed in normal seminiferous tubules and in the interstitial compartment. EL m....... The results suggest that both EL and LPL participate in the supply of nutrients and steroidogenesis in the testes, and that especially EL may be important for the supply of cholesterol for testosterone production in the Leydig cells. The partial cellular separation of the expression of the two lipases...

  15. Glucose-dependent insulinotropic polypeptide has impaired effect on abdominal, subcutaneous adipose tissue metabolism in obese subjects

    DEFF Research Database (Denmark)

    Asmar, M; Simonsen, L; Arngrim, N;

    2013-01-01

    that increased GIP secretion in obesity will promote lipid deposition in adipose tissue. In light of the current attempts to employ GIP antagonists in the treatment and prevention of human obesity, the present experiments were performed in order to elucidate whether the adipose tissue lipid metabolism...... would be enhanced or blunted during a GIP, hyperinsulinemic and hyperglycemic (HI-HG) clamp in obese subjects with either normal glucose tolerance (NGT) or impaired glucose tolerance (IGT). DESIGN: Sixteen obese (BMI>30 kg m(-2)) subjects were divided into two groups, based on their plasma glucose...... deposition in adipose tissue under the applied experimental conditions and likewise the circulating triglyceride (TAG) concentrations remained constant. CONCLUSION: The applied GIP, HI-HG clamp did not induce any changes in TAG uptake in adipose tissue in obese subjects. This may be due to a blunted increase...

  16. Brown Adipose Tissue Activation Is Linked to Distinct Systemic Effects on Lipid Metabolism in Humans.

    Science.gov (United States)

    Chondronikola, Maria; Volpi, Elena; Børsheim, Elisabet; Porter, Craig; Saraf, Manish K; Annamalai, Palam; Yfanti, Christina; Chao, Tony; Wong, Daniel; Shinoda, Kosaku; Labbė, Sebastien M; Hurren, Nicholas M; Cesani, Fernardo; Kajimura, Shingo; Sidossis, Labros S

    2016-06-14

    Recent studies suggest that brown adipose tissue (BAT) plays a role in energy and glucose metabolism in humans. However, the physiological significance of human BAT in lipid metabolism remains unknown. We studied 16 overweight/obese men during prolonged, non-shivering cold and thermoneutral conditions using stable isotopic tracer methodologies in conjunction with hyperinsulinemic-euglycemic clamps and BAT and white adipose tissue (WAT) biopsies. BAT volume was significantly associated with increased whole-body lipolysis, triglyceride-free fatty acid (FFA) cycling, FFA oxidation, and adipose tissue insulin sensitivity. Functional analysis of BAT and WAT demonstrated the greater thermogenic capacity of BAT compared to WAT, while molecular analysis revealed a cold-induced upregulation of genes involved in lipid metabolism only in BAT. The accelerated mobilization and oxidation of lipids upon BAT activation supports a putative role for BAT in the regulation of lipid metabolism in humans. PMID:27238638

  17. Physiological adaptations in adipose tissue of Brahman vs Angus heifers.

    Science.gov (United States)

    Sprinkle, J E; Hansard, H S; Warrington, B G; Holloway, J W; Wu, G; Smith, S B

    1998-03-01

    Nonpregnant yearling Brahman (n = 12) and Angus (n = 12) heifers were equally allocated to two dietary treatments in a replicated study to examine responses in lipid metabolism to nutritional treatments consisting of a moderate energy diet (2.0 Mcal ME/kg) fed at maintenance and a 2.5 x maintenance high-energy diet (2.4 Mcal ME/kg) fed for 30 d. In vitro lipogenesis and the activities of lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) were determined in perianal subcutaneous adipose tissue biopsies at the start and end of the trial. At the start of the trial, breeds had similar (P > .10) rates of lipogenesis and LPL activity. Brahman had greater (P Angus at the start of the trial and tended (P .10) HSL activity. Heifers on the high-energy, higher-intake diet had greater lipogenesis (P .10) rates of lipogenesis at the end of the trial. When adjusted for BCS nested within breed, Brahman had greater (P Angus. PMID:9535333

  18. Lipase biocatalysis for useful biodegradable products

    Energy Technology Data Exchange (ETDEWEB)

    Linko, Y.Y.; Wang, Zhuo Lin; Uosukainen, E.; Seppaelae, J. [Helsinki Univ. of Technology, Espoo (Finland); Laemsae, M. [Raisio Group Oil Milling Industry, Raisio (Finland)

    1996-12-31

    It was shown that lipases can be used as biocatalysts in the production of useful biodegradable compounds such as 1-butyl oleate by direct esterification of butanol and oleic acid to decrease viscosity of biodiesel in winter use. By enzymic transesterification, a mixture of 2-ethyl-1-hexyl esters from rapeseed oil fatty acids can be obtained in good yields for use as a solvent, and of trimethylolpropane esters for use as a lubricant. Finally, it was demonstrated that polyesters with a mass average molar mass in excess of 75,000 g mol{sup -}1 can be obtained by esterification or transesterification by using lipase as biocatalyst. (author) (3 refs.)

  19. Characterization of Cross-Linked Lipase Aggregates

    DEFF Research Database (Denmark)

    Prabhavathi Devi, Bethala Lakshmi Anu; Guo, Zheng; Xu, Xuebing

    2009-01-01

    Commercially available microbial lipases from different sources were immobilized as cross-linked enzyme aggregates (CLEAs) using different precipitants and glutaraldehyde as cross-linkers. These CLEAs were assayed based on esterification between lauric acid and n-propanol in solvent-free systems....... Precipitants were found to have a profound influence on both specific activities and total activity recovery of CLEAs, as exemplified by Candida antarctica lipase B (CALB). Among the CLEAs of CALB studied, those obtained using PEG600, ammonium sulfate, PEG200 and acetone as precipitants were observed to attain...

  20. Cardiac expression of microsomal triglyceride transfer protein is increased in obesity and serves to attenuate cardiac triglyceride accumulation

    DEFF Research Database (Denmark)

    Bartels, Emil D; Nielsen, Jan M; Hellgren, Lars I;

    2009-01-01

    Obesity causes lipid accumulation in the heart and may lead to lipotoxic heart disease. Traditionally, the size of the cardiac triglyceride pool is thought to reflect the balance between uptake and beta-oxidation of fatty acids. However, triglycerides can also be exported from cardiomyocytes via...... secretion of apolipoproteinB-containing (apoB) lipoproteins. Lipoprotein formation depends on expression of microsomal triglyceride transfer protein (MTP); the mouse expresses two isoforms of MTP, A and B. Since many aspects of the link between obesity-induced cardiac disease and cardiac lipid metabolism...... remain unknown, we investigated how cardiac lipoprotein synthesis affects cardiac expression of triglyceride metabolism-controlling genes, insulin sensitivity, and function in obese mice. Heart-specific ablation of MTP-A in mice using Cre-loxP technology impaired upregulation of MTP expression...

  1. Impact of physical inactivity on subcutaneous adipose tissue metabolism in healthy young male offspring of patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Højbjerre, Lise; Sonne, MP; Alibegovic, AC;

    2010-01-01

    was to investigate the impact of physical inactivity on adipose tissue (AT) metabolism in FDR subjects. RESEARCH DESIGN AND METHODS A total of 13 FDR and 20 control (CON) subjects participated in the study. All were studied before and after 10 days of bed rest using the glucose clamp technique combined...... with measurements of glucose uptake, lipolysis, and lactate release from subcutaneous abdominal (SCAAT) and femoral (SCFAT) adipose tissue by the microdialysis technique. Additionally, mRNA expression of lipases was determined in biopsies from SCAAT. RESULTS Before bed rest, the FDR subjects revealed significantly...... normal glucose tolerance (5). The metabolic defects include insufficient insulin secretion (6), decreased peripheral glucose uptake (7), and the impaired antilipolytic effect of insulin in subcutaneous adipose tissue (AT) (8). AT is an active compartment in the lipid and glucose metabolism of humans...

  2. ATGL has a key role in lipid droplet/adiposome degradation in mammalian cells

    OpenAIRE

    Smirnova, Elena; Goldberg, Elysa B; Makarova, Kira S; Lin, Lin; Brown, William J.; Jackson, Catherine L.

    2005-01-01

    Lipid droplets (LDs), also called adiposomes, are found in many eukaryotic cells, and are highly upregulated in lipid-storage cells, such as adipocytes. The mechanism by which adiposomes and their component neutral lipids are degraded is an important health issue with the rapidly spreading epidemic of obesity. Recently, a novel triglyceride lipase (adipose triglyceride lipase (ATGL)) that catalyses the initial step in triglyceride hydrolysis in adipocyte LDs was identified. Here, we show that...

  3. Bioengineering Beige Adipose Tissue Therapeutics.

    Science.gov (United States)

    Tharp, Kevin M; Stahl, Andreas

    2015-01-01

    Unlocking the therapeutic potential of brown/beige adipose tissue requires technological advancements that enable the controlled expansion of this uniquely thermogenic tissue. Transplantation of brown fat in small animal model systems has confirmed the expectation that brown fat expansion could possibly provide a novel therapeutic to combat obesity and related disorders. Expansion and/or stimulation of uncoupling protein-1 (UCP1)-positive adipose tissues have repeatedly demonstrated physiologically beneficial reductions in circulating glucose and lipids. The recent discovery that brown adipose tissue (BAT)-derived secreted factors positively alter whole body metabolism further expands potential benefits of brown or beige/brite adipose expansion. Unfortunately, there are no sources of transplantable BATs for human therapeutic purposes at this time. Recent developments in bioengineering, including novel hyaluronic acid-based hydrogels, have enabled non-immunogenic, functional tissue allografts that can be used to generate large quantities of UCP1-positive adipose tissue. These sophisticated tissue-engineering systems have provided the methodology to develop metabolically active brown or beige/brite adipose tissue implants with the potential to be used as a metabolic therapy. Unlike the pharmacological browning of white adipose depots, implantation of bioengineered UCP1-positive adipose tissues offers a spatially controlled therapeutic. Moving forward, new insights into the mechanisms by which extracellular cues govern stem-cell differentiation and progenitor cell recruitment may enable cell-free matrix implant approaches, which generate a niche sufficient to recruit white adipose tissue-derived stem cells and support their differentiation into functional beige/brite adipose tissues. This review summarizes clinically relevant discoveries in tissue-engineering and biology leading toward the recent development of biomaterial supported beige adipose tissue implants and

  4. Bioengineering Beige Adipose Tissue Therapeutics.

    Science.gov (United States)

    Tharp, Kevin M; Stahl, Andreas

    2015-01-01

    Unlocking the therapeutic potential of brown/beige adipose tissue requires technological advancements that enable the controlled expansion of this uniquely thermogenic tissue. Transplantation of brown fat in small animal model systems has confirmed the expectation that brown fat expansion could possibly provide a novel therapeutic to combat obesity and related disorders. Expansion and/or stimulation of uncoupling protein-1 (UCP1)-positive adipose tissues have repeatedly demonstrated physiologically beneficial reductions in circulating glucose and lipids. The recent discovery that brown adipose tissue (BAT)-derived secreted factors positively alter whole body metabolism further expands potential benefits of brown or beige/brite adipose expansion. Unfortunately, there are no sources of transplantable BATs for human therapeutic purposes at this time. Recent developments in bioengineering, including novel hyaluronic acid-based hydrogels, have enabled non-immunogenic, functional tissue allografts that can be used to generate large quantities of UCP1-positive adipose tissue. These sophisticated tissue-engineering systems have provided the methodology to develop metabolically active brown or beige/brite adipose tissue implants with the potential to be used as a metabolic therapy. Unlike the pharmacological browning of white adipose depots, implantation of bioengineered UCP1-positive adipose tissues offers a spatially controlled therapeutic. Moving forward, new insights into the mechanisms by which extracellular cues govern stem-cell differentiation and progenitor cell recruitment may enable cell-free matrix implant approaches, which generate a niche sufficient to recruit white adipose tissue-derived stem cells and support their differentiation into functional beige/brite adipose tissues. This review summarizes clinically relevant discoveries in tissue-engineering and biology leading toward the recent development of biomaterial supported beige adipose tissue implants and

  5. Bioengineering beige adipose tissue therapeutics

    Directory of Open Access Journals (Sweden)

    Kevin eTharp

    2015-10-01

    Full Text Available Unlocking the therapeutic potential of brown/beige adipose tissue requires technological advancements that enable the controlled expansion of this uniquely thermogenic tissue. Transplantation of brown fat in small animal model systems has confirmed the expectation that brown fat expansion could possibly provide a novel therapeutic to combat obesity and related disorders. Expansion and/or stimulation of UCP1-positive adipose tissues have repeatedly demonstrated physiologically beneficial reductions in circulating glucose and lipids. The recent discovery that brown adipose tissue-derived secreted factors positively alter whole body metabolism further expands potential benefits of brown or beige/brite adipose expansion. Unfortunately, there are no sources of transplantable brown adipose tissues for human therapeutic purposes at this time.Recent developments in bioengineering, including novel hyaluronic acid based hydrogels, have enabled non-immunogenic, functional tissue allografts that can be used to generate large quantities of UCP1-positive adipose tissue. These sophisticated tissue-engineering systems have provided the methodology to develop metabolically active brown or beige/brite adipose tissue implants with the potential to be used as a metabolic therapy. Unlike the pharmacological browning of white adipose depots, implantation of bioengineered UCP1-positive adipose tissues offers a spatially controlled therapeutic. Moving forward, new insights into the mechanisms by which extracellular cues govern stem cell differentiation and progenitor cell recruitment may enable cell-free matrix implant approaches, which generate a niche sufficient to recruit WAT derived stem cells and support their differentiation into functional beige/brite adipose tissues. This review summarizes clinically relevant discoveries in tissue-engineering and biology leading toward the recent development of beige adipose tissue implants and their potential for the metabolic

  6. Fascia Origin of Adipose Cells.

    Science.gov (United States)

    Su, Xueying; Lyu, Ying; Wang, Weiyi; Zhang, Yanfei; Li, Danhua; Wei, Suning; Du, Congkuo; Geng, Bin; Sztalryd, Carole; Xu, Guoheng

    2016-05-01

    Adipocytes might arise from vascular stromal cells, pericytes and endothelia within adipose tissue or from bone marrow cells resident in nonadipose tissue. Here, we identified adipose precursor cells resident in fascia, an uninterrupted sheet of connective tissue that extends throughout the body. The cells and fragments of superficial fascia from the rat hindlimb were highly capable of spontaneous and induced adipogenic differentiation but not myogenic and osteogenic differentiation. Fascial preadipocytes expressed multiple markers of adipogenic progenitors, similar to subcutaneous adipose-derived stromal cells (ASCs) but discriminative from visceral ASCs. Such preadipocytes resided in fascial vasculature and were physiologically active in vivo. In growing rats, adipocytes dynamically arose from the adventitia to form a thin adipose layer in the fascia. Later, some adipocytes appeared to overlay on top of other adipocytes, an early sign for the formation of three-dimensional adipose tissue in fascia. The primitive adipose lobules extended invariably along blood vessels toward the distal fascia areas. At the lobule front, nascent capillaries wrapped and passed ahead of mature adipocytes to form the distal neovasculature niche, which might replenish the pool of preadipocytes and supply nutrients and hormones necessary for continuous adipogenesis. Our findings suggest a novel model for the origin of adipocytes from the fascia, which explains both neogenesis and expansion of adipose tissue. Fascial preadipocytes generate adipose cells to form primitive adipose lobules in superficial fascia, a subcutaneous nonadipose tissue. With continuous adipogenesis, these primitive adipose lobules newly formed in superficial fascia may be the rudiment of subcutaneous adipose tissue. Stem Cells 2016;34:1407-1419.

  7. Contractions induce phosphorylation of the AMPK site Ser565 in hormone-sensitive lipase in muscle

    DEFF Research Database (Denmark)

    Donsmark, Morten; Langfort, Jozef; Holm, Cecilia;

    2004-01-01

    Intramyocellular triglyceride is an important energy store which is related to insulin resistance. Mobilization of fatty acids from this pool is probably regulated by hormone-sensitive lipase (HSL), which has recently been shown to exist in muscle and to be activated by epinephrine via PKA...... and by contractions via PKC and ERK. 5' AMP-activated protein kinase (AMPK) is an intracellular fuel gauge which regulates metabolism. In this study we incubated rat soleus muscle to investigate if AMPK influences HSL during 5min of repeated tetanic contractions. An eightfold increase in AMPK activity was accompanied...... by a 2.5-fold increase in phosphorylation of the AMPK-site Ser(565) in HSL (pHSL activation while HSL-Ser(565) phosphorylation was not reduced. The study indicates that during contractions AMPK phosphorylates HSL in Ser(565...

  8. Hormone-sensitive lipase deficiency suppresses insulin secretion from pancreatic islets of Lepob/ob mice

    International Nuclear Information System (INIS)

    It has long been a matter of debate whether the hormone-sensitive lipase (HSL)-mediated lipolysis in pancreatic β-cells can affect insulin secretion through the alteration of lipotoxicity. We generated mice lacking both leptin and HSL (Lepob/ob/HSL-/-) and explored the role of HSL in pancreatic β-cells in the setting of obesity. Lepob/ob/HSL-/- developed elevated blood glucose levels and reduced plasma insulin levels compared with Lepob/ob/HSL+/+ in a fed state, while the deficiency of HSL did not affect glucose homeostasis in Lep+/+ background. The deficiency of HSL exacerbated the accumulation of triglycerides in Lepob/ob islets, leading to reduced glucose-stimulated insulin secretion. The deficiency of HSL also diminished the islet mass in Lepob/ob mice due to decreased cell proliferation. In conclusion, HSL affects insulin secretary capacity especially in the setting of obesity.

  9. Hepatic Lipase: a Comprehensive View of its Role on Plasma Lipid and Lipoprotein Metabolism.

    Science.gov (United States)

    Kobayashi, Junji; Miyashita, Kazuya; Nakajima, Katsuyuki; Mabuchi, Hiroshi

    2015-01-01

    Hepatic lipase (HL) is a key enzyme catalyzing the hydrolysis of triglycerides (TG) and phospholipids (PLs) in several lipoproteins. It is generally recognized that HL is involved in the remodeling of remnant, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and the production of small, dense low-density lipoproteins (sd-LDLs).On the other hand, it is unclear whether HL accelerates or retards atherosclerosis. From the clinical point of view, HL deficiency may provide useful information on answering this question, but the rarity of this disease makes it impossible to conduct epidemiological study.In this review, we describe a comprehensive and updated view of the clinical significance of HL on lipid and lipoprotein metabolism. PMID:26194979

  10. Triglyceride Glucose-Body Mass Index Is a Simple and Clinically Useful Surrogate Marker for Insulin Resistance in Nondiabetic Individuals.

    Directory of Open Access Journals (Sweden)

    Leay-Kiaw Er

    Full Text Available Insulin resistance (IR and the consequences of compensatory hyperinsulinemia are pathogenic factors for a set of metabolic abnormalities, which contribute to the development of diabetes mellitus and cardiovascular diseases. We compared traditional lipid levels and ratios and combined them with fasting plasma glucose (FPG levels or adiposity status for determining their efficiency as independent risk factors for IR.We enrolled 511 Taiwanese individuals for the analysis. The clinical usefulness of various parameters--such as traditional lipid levels and ratios; visceral adiposity indicators, visceral adiposity index (VAI, and lipid accumulation product (LAP; the product of triglyceride (TG and FPG (the TyG index; TyG with adiposity status (TyG-body mass index [BMI] and TyG-waist circumference index [WC]; and adipokine levels and ratios--was analyzed to identify IR.For all lipid ratios, the TG/high-density lipoprotein cholesterol (HDL-C ratio had the highest additional percentage of variation in the homeostasis model assessment of insulin resistance (HOMA-IR; 7.0% in total; for all variables of interest, TyG-BMI and leptin-adiponectin ratio (LAR were strongly associated with HOMA-IR, with 16.6% and 23.2% of variability, respectively. A logistic regression analysis revealed similar patterns. A receiver operating characteristic (ROC curve analysis indicated that TG/HDL-C was a more efficient IR discriminator than other lipid variables or ratios. The area under the ROC curve (AUC for VAI (0.734 and TyG (0.708 was larger than that for TG/HDL-C (0.707. TyG-BMI and LAR had the largest AUC (0.801 and 0.801, respectively.TyG-BMI is a simple, powerful, and clinically useful surrogate marker for early identification of IR.

  11. Anti-obesity activity of hen egg anti-lipase immunoglobulin yolk, a novel pancreatic lipase inhibitor

    OpenAIRE

    Hirose, Mai; Ando, Taishi; Shofiqur, Rahman; Umeda, Kouji; Kodama, Yoshikatsu; Van Nguyen, Sa; Goto, Tsuyoshi; Shimada, Masaya; Nagaoka, Satoshi

    2013-01-01

    Background There is completely no report about both hen egg anti-lipase immunoglobulin yolk (IgY) and its anti-obesity action. Thus, we tried to isolate and characterize a novel anti-lipase immunoglobulin from hen egg yolk. Moreover, we investigated whether hen egg yolk anti-lipase IgY inhibits pancreatic lipase activity in vitro, and examined its ability to prevent obesity in a murine high fat diet-induced obesity model. Methods We determined the inhibitory action of Anti-lipase IgY on lipas...

  12. Immobilization of a Commercial Lipase from Penicillium camembertii (Lipase G) by Different Strategies

    OpenAIRE

    Adriano A. Mendes; Larissa Freitas; de Carvalho, Ana Karine F.; de Oliveira, Pedro C.; Heizir F. de Castro

    2011-01-01

    The objective of this work was to select the most suitable procedure to immobilize lipase from Penicillium camembertii (Lipase G). Different techniques and supports were evaluated, including physical adsorption on hydrophobic supports octyl-agarose, poly(hydroxybutyrate) and Amberlite resin XAD-4; ionic adsorption on the anionic exchange resin MANAE-agarose and covalent attachment on glyoxyl-agarose, MANAE-agarose cross-linked with glutaraldehyde, MANAE-agarose-glutaraldehyde, and epoxy-silic...

  13. Differential modulation of the functionality of white adipose tissue of obese Zucker (fa/fa) rats by the type of protein and the amount and type of fat.

    Science.gov (United States)

    Díaz-Villaseñor, Andrea; Granados, Omar; González-Palacios, Berenice; Tovar-Palacio, Claudia; Torre-Villalvazo, Ivan; Olivares-García, Verónica; Torres, Nimbe; Tovar, Armando R

    2013-11-01

    Recent evidence indicates that several metabolic abnormalities developed during obesity are associated with the presence of dysfunctional adipose tissue. Diet is a key factor that modulates several functions of adipose tissue; however, each nutrient in the diet produces specific changes. Thus, the aim of this work was to study the effect of the interaction of the type (coconut or soybean oil) and amount (5% or 10%) of fat with the type of dietary protein (casein or soy protein) on the functionality of white adipose tissue of Zucker (fa/fa) rats. The results showed that soybean oil reduced adipocyte size and decreased esterified saturated fatty acids in white adipose tissue. Excess dietary fat also modified the composition of esterified fatty acids in white adipose tissue, increased the secretion of saturated fatty acids to serum from white adipose tissue and reduced the process of fatty acids re-esterification. On the other hand, soy protein sensitized the activation of the hormone-sensitive lipase by increasing the phosphorylation of this enzyme (Ser 563) despite rats fed soy protein were normoglucagonemic, in contrast with rats fed casein that showed hyperglucagonemia but reduced hormone-sensitive lipase phosphorylation. Finally, in white adipose tissue, the interaction between the tested dietary components modulated the transcription/translation process of lipid and carbohydrate metabolism genes via the activity of the PERK-endoplasmic reticulum stress response. Therefore, our results showed that the type of protein and the type and amount of dietary fat selectively modify the activity of white adipose tissue, even in a genetic model of obesity.

  14. Methodologies to assess paediatric adiposity.

    LENUS (Irish Health Repository)

    Horan, M

    2014-05-04

    Childhood obesity is associated with increased risk of adult obesity, cardiovascular disease, diabetes and cancer. Appropriate techniques for assessment of childhood adiposity are required to identify children at risk. The aim of this review was to examine core clinical measurements and more technical tools to assess paediatric adiposity.

  15. Lagenaria siceraria ameliorates atheromatous lesions by modulating HMG-CoA reductase and lipoprotein lipase enzymes activity in hypercholesterolemic rats

    Institute of Scientific and Technical Information of China (English)

    Mithun Singh Rajput; Neelam Balekar; Dinesh Kumar Jain

    2014-01-01

    Objective:To investigate the antiatherosclerotic potential ofLagenaria siceraria(L. siceraria) by calculating percentage plaque area in aorta and grade of atheromatous lesions modulated byHMG-CoA reductase enzyme and lipoprotein lipase enzymes levels in hyperlipidemic rats. Methods:Rats were divided into different groups, fed with high cholesterol atherogenic diet and in addition supplemented with ethanolic extract of fruits ofL. siceraria and standard drug atorvastatin.At the end of the treatment schedule, the atherosclerotic lesion area was measured in cross-sections of the aortic root and grading of atherosclerotic lesions was done.The blood samples from animals of different groups were evaluated for serum lipid profile determination and plasma lipoprotein lipase activity and the hepaticHMG-CoA activity was also determined. Results:Treatment of rats with ethanolic extract of fruits ofL. siceraria significantly lowers the risk of atherosclerosis by lowering percentage plaque area in aorta and grade of atheromatous lesions in hypercholesterolemic rats and also serum cholesterol, triglyceride,LDL-c,VLDL-c and increasedHDL-c levels as well.The extract also induced lipoprotein lipase activity and significantly decreased cholesterogenesis inliver by reducingHMG-CoA reductase activity in hypercholeaterolemic rats.Conclusion:It can be concluded that ethanolic extract of fruits of L. siceraria contains active components which ameliorates the atheromatous lesions in rat aorta and lowers the risk of atherosclerosis in hypercholesterolemic rats.

  16. New Extremophilic Lipases and Esterases from Metagenomics

    Science.gov (United States)

    López-López, Olalla; Cerdán, Maria E; González Siso, Maria I

    2014-01-01

    Lipolytic enzymes catalyze the hydrolysis of ester bonds in the presence of water. In media with low water content or in organic solvents, they can catalyze synthetic reactions such as esterification and transesterification. Lipases and esterases, in particular those from extremophilic origin, are robust enzymes, functional under the harsh conditions of industrial processes owing to their inherent thermostability and resistance towards organic solvents, which combined with their high chemo-, regio- and enantioselectivity make them very attractive biocatalysts for a variety of industrial applications. Likewise, enzymes from extremophile sources can provide additional features such as activity at extreme temperatures, extreme pH values or high salinity levels, which could be interesting for certain purposes. New lipases and esterases have traditionally been discovered by the isolation of microbial strains producing lipolytic activity. The Genome Projects Era allowed genome mining, exploiting homology with known lipases and esterases, to be used in the search for new enzymes. The Metagenomic Era meant a step forward in this field with the study of the metagenome, the pool of genomes in an environmental microbial community. Current molecular biology techniques make it possible to construct total environmental DNA libraries, including the genomes of unculturable organisms, opening a new window to a vast field of unknown enzymes with new and unique properties. Here, we review the latest advances and findings from research into new extremophilic lipases and esterases, using metagenomic approaches, and their potential industrial and biotechnological applications. PMID:24588890

  17. Structural characterization of MAPLE deposited lipase biofilm

    Science.gov (United States)

    Aronne, Antonio; Ausanio, Giovanni; Bloisi, Francesco; Calabria, Raffaela; Califano, Valeria; Fanelli, Esther; Massoli, Patrizio; Vicari, Luciano R. M.

    2014-11-01

    Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography-mass spectrometry gave results consistent with undamaged deposition of lipase.

  18. Polyphenolic Compounds as Pancreatic Lipase Inhibitors.

    Science.gov (United States)

    Buchholz, Tina; Melzig, Matthias F

    2015-07-01

    Obesity and its associated diseases such as diabetes mellitus and coronary heart diseases are a major challenge for our society. An important target for the treatment of obesity includes the development of inhibitors of nutrient digestion and absorption. Inhibition of pancreatic lipase and the associated reduction of lipid absorption is an attractive approach for the discovery of potent agents. Currently, the only clinically approved pharmacologic agent as pancreatic lipase inhibitor is Orlistat. However, its usage is compromised by unpleasant gastrointestinal adverse reactions (oily stools, oily spotting, flatulence). The use of botanical materials as a potential source of new drugs is of increasing importance and application. Natural products that are interesting for obesity treatment are generally considered to have less toxic and side effects than totally synthetic drugs. One of the most important sources of potential pancreatic lipase inhibitors represents the class of polyphenols. This article summarizes most studied subclasses of polyphenols including flavonoids, hydroxycinnamic acids, hydroxybenzoic acids and lignans with pancreatic lipase inhibitory effects. A structural comparison of potent inhibitors shows an increased inhibitory effect depending on number and position of phenolic hydroxyl groups, degree of polymerization and elimination of glycosylation during digestion. PMID:26132857

  19. Amylase and lipase values in normal subjects

    NARCIS (Netherlands)

    Riet, H.G. van

    1968-01-01

    In 146 hospitalized individuals (71 men and 75 women), the simultaneous fasting serum amylase and lipase concentrations and the urinary amylase excretion per 24 h were determined. Patients with pancreatic abnormalities or other diseases which might produce abnormal enzyme values were ruled out from

  20. Lipoprotein lipase isoelectric point isoforms in humans

    DEFF Research Database (Denmark)

    Badia-Villanueva, M.; Carulla, P.; Carrascal, M.;

    2014-01-01

    Lipoprotein lipase (LPL) hydrolyzes circulating triacylglycerols (TAG) into free fatty acids and glycerol. It is present in almost all tissues and its tissue-specific regulation directs the flow of circulating TAG in the body. We demonstrated in a previous study that, in rat heart and post...

  1. Gastric Lipase Secretion in Children with Gastritis

    Directory of Open Access Journals (Sweden)

    Krystyna Sztefko

    2013-07-01

    Full Text Available Gastric lipase is one of the prepancreatic lipases found in some mammalian species and in humans. Our knowledge of the hormonal regulation of gastric lipase secretion in children and adolescents is still very limited. The aim of this study was to compare the activity of human gastric lipase (HGL in gastric juice in healthy adolescents and in patients with gastritis. The adolescents were allocated to three groups: the first including patients with Helicobacter pylori gastritis (HPG; n = 10, the second including patients with superficial gastritis caused by pathogens other than H. pylori (non-HPG; n = 14 and the control group including healthy adolescents (n = 14. Activity of HGL was measured in gastric juice collected during endoscopy. Plasma concentrations of cholecystokinin (CCK, glucagon-like peptide-1 (GLP-1 and glucose-dependent insulinotropic peptide (GIP were measured in all adolescents. Activity of HGL in the non-HPG group was significantly lower than in the HPG group (p < 0.005 and the control group (p < 0.005. Mean plasma GIP levels in the control group were lower than in the non-HPG group (p < 0.003 and the HPG group (p < 0.01. We conclude that the regulation of HGL secretion by GLP-1 and CCK is altered in patients with gastritis. Moreover, GIP is a potent controller of HGL activity, both in healthy subjects and in patients with gastritis.

  2. Microbial lipases: Production, properties and biotechnological applications

    Directory of Open Access Journals (Sweden)

    Josana Maria Messias

    2011-09-01

    Full Text Available Lipases belong to the group of hydrolases that catalyze the hydrolysis of triacylglycerol lipids to free fatty acids and glycerol. They have significant potential biotechnological applications in catalyzing organic synthesis reactions in non-aqueous solvents using simplified procedures resulting in conversions of high yields. Lipase production has conventionally been performed by submerged fermentation; however, solid-state fermentation processes have been prominent when residues are used as substrates because they serve as low-cost nutrient sources. Microbial lipases can be used as additives in foods to modify and enhance organoleptic properties, as well as in detergents to hydrolyse fats in the treatment of oily effluents, and also have value for pharmaceutical, cosmetic, agrochemical, and oil chemical industries. More recently, they are used in transesterification reactions to convert plant seed oils into biodiesel. The objective of this work was to review the published literature on the production, properties and applications of microbial lipases, and its biotechnological role in producing biodiesel.

  3. KARAKTERISASI SIFAT-SIFAT BIOKIMIA EKSTRAK KASAR LIPASE EKSTRASELULER BAKTERI Azospirillum sp.PRD1

    OpenAIRE

    Santi Nur Handayani; Puji Lestari; Oedjijono; Tri Joko Raharjo; Sabirin Matsjeh

    2011-01-01

    Enzim lipase mempunyai peranan penting dalam katalis berbagai reaksi industri satu diantaranya pembuatan flavor melalui reaksi esterifikasi. Lipase adalah biokatalis yang berperan besar dalam aplikasi bioteknologi, seperti dalam sintesis biopolimer, biodiesel, produksi obat, dan produksi flavor. Peningkatan penggunaan lipase untuk industri mendorong dilakukan penelitian untuk mendapatkan sumber-sumber lipase baru. Sumber lipase yang potensial salah satunya adalah bakteri Azospirillum sp.PRD1 ...

  4. New eutectic ionic liquids for lipase activation and enzymatic preparation of biodiesel†

    Science.gov (United States)

    Zhao, Hua; Baker, Gary A.; Holmes, Shaletha

    2012-01-01

    The enzymatic preparation of biodiesel has been hampered by the lack of suitable solvents with desirable properties such as high lipase compatibility, low cost, low viscosity, high biodegradability, and ease of product separation. Recent interest in using ionic liquids (ILs) as advanced reaction media has led to fast reaction rates and high yields in the enzymatic synthesis of biodiesel. However, conventional (i.e., cation–anion paired) ILs based on imidazolium and other quaternary ammonium salts remain too expensive for wide application at industrial scales. In this study, we report on newly-synthesized eutectic ILs derived from choline acetate or choline chloride coupled with biocompatible hydrogen-bond donors, such as glycerol. These eutectic solvents have favorable properties including low viscosity, high biodegradability, and excellent compatibility with Novozym® 435, a commercial immobilized Candida antarctica lipase B. Furthermore, in a model biodiesel synthesis system, we demonstrate high reaction rates for the enzymatic transesterification of Miglyol® oil 812 with methanol, catalyzed by Novozym® 435 in choline acetate/glycerol (1 : 1.5 molar ratio). The high conversion (97%) of the triglyceride obtained within 3 h, under optimal conditions, suggests that these novel eutectic solvents warrant further exploration as potential media in the enzymatic production of biodiesel. PMID:21283901

  5. Structural insights into methanol-stable variants of lipase T6 from Geobacillus stearothermophilus.

    Science.gov (United States)

    Dror, Adi; Kanteev, Margarita; Kagan, Irit; Gihaz, Shalev; Shahar, Anat; Fishman, Ayelet

    2015-11-01

    Enzymatic production of biodiesel by transesterification of triglycerides and alcohol, catalyzed by lipases, offers an environmentally friendly and efficient alternative to the chemically catalyzed process while using low-grade feedstocks. Methanol is utilized frequently as the alcohol in the reaction due to its reactivity and low cost. However, one of the major drawbacks of the enzymatic system is the presence of high methanol concentrations which leads to methanol-induced unfolding and inactivation of the biocatalyst. Therefore, a methanol-stable lipase is of great interest for the biodiesel industry. In this study, protein engineering was applied to substitute charged surface residues with hydrophobic ones to enhance the stability in methanol of a lipase from Geobacillus stearothermophilus T6. We identified a methanol-stable variant, R374W, and combined it with a variant found previously, H86Y/A269T. The triple mutant, H86Y/A269T/R374W, had a half-life value at 70 % methanol of 324 min which reflects an 87-fold enhanced stability compared to the wild type together with elevated thermostability in buffer and in 50 % methanol. This variant also exhibited an improved biodiesel yield from waste chicken oil compared to commercial Lipolase 100L® and Novozyme® CALB. Crystal structures of the wild type and the methanol-stable variants provided insights regarding structure-stability correlations. The most prominent features were the extensive formation of new hydrogen bonds between surface residues directly or mediated by structural water molecules and the stabilization of Zn and Ca binding sites. Mutation sites were also characterized by lower B-factor values calculated from the X-ray structures indicating improved rigidity.

  6. Structure of Human Pancreatic Lipase-Related Protein 2 with the Lid in an Open Conformation

    Energy Technology Data Exchange (ETDEWEB)

    Eydoux, Cecilia; Spinelli, Silvia; Davis, Tara L.; Walker, John R.; Seitova, Alma; Dhe-Paganon, Sirano; De Caro, Alain; Cambillau, Christian; Carriere, Frederic (CNRS-UMR); (Toronto)

    2008-10-02

    Access to the active site of pancreatic lipase (PL) is controlled by a surface loop, the lid, which normally undergoes conformational changes only upon addition of lipids or amphiphiles. Structures of PL with their lids in the open and functional conformation have required cocrystallization with amphiphiles. Here we report two crystal structures of wild-type and unglycosylated human pancreatic lipase-related protein 2 (HPLRP2) with the lid in an open conformation in the absence of amphiphiles. These structures solved independently are strikingly similar, with some residues of the lid being poorly defined in the electron-density map. The open conformation of the lid is however different from that previously observed in classical liganded PL, suggesting different kinetic properties for HPLRP2. Here we show that the HPLRP2 is directly inhibited by E600, does not present interfacial activation, and acts preferentially on substrates forming monomers or small aggregates (micelles) dispersed in solution like monoglycerides, phospholipids and galactolipids, whereas classical PL displays reverse properties and a high specificity for unsoluble substrates like triglycerides and diglycerides forming oil-in-water interfaces. These biochemical properties imply that the lid of HPLRP2 is likely to spontaneously adopt in solution the open conformation observed in the crystal structure. This open conformation generates a large cavity capable of accommodating the digalactose polar head of galactolipids, similar to that previously observed in the active site of the guinea pig PLRP2, but absent from the classical PL. Most of the structural and kinetic properties of HPLRP2 were found to be different from those of rat PLRP2, the structure of which was previously obtained with the lid in a closed conformation. Our findings illustrate the essential role of the lid in determining the substrate specificity and the mechanism of action of lipases.

  7. Ionic liquids increase the catalytic efficiency of a lipase (Lip1) from an antarctic thermophilic bacterium.

    Science.gov (United States)

    Muñoz, Patricio A; Correa-Llantén, Daniela N; Blamey, Jenny M

    2015-01-01

    Lipases catalyze the hydrolysis and synthesis of triglycerides and their reactions are widely used in industry. The use of ionic liquids has been explored in order to improve their catalytic properties. However, the effect of these compounds on kinetic parameters of lipases has been poorly understood. A study of the kinetic parameters of Lip1, the most thermostable lipase from the supernatant of the strain ID17, a thermophilic bacterium isolated from Deception Island, Antarctica, and a member of the genus Geobacillus is presented. Kinetic parameters of Lip1 were modulated by the use of ionic liquids BmimPF6 and BmimBF4. The maximum reaction rate of Lip1 was improved in the presence of both salts. The highest effect was observed when BmimPF6 was added in the reaction mix, resulting in a higher hydrolytic activity and in a modulation of the catalytic efficiency of the enzyme. However, the catalytic efficiency did not change in the presence of BmimBF4. The increase of the reaction rates of Lip1 promoted by these ionic liquids could be related to possible changes in the Lip1 structure. This effect was measured by quenching of tryptophan fluorescence of the enzyme, when it was incubated with each liquid salt. In conclusion, the hydrolytic activity of Lip1 is modulated by the ionic liquids BmimBF4 and BmimPF6, improving the reaction rate and the catalytic efficiency of this enzyme when BmimPF6 was used. This effect is probably due to changes in the structure of Lip1 induced by the presence of these ionic liquids, stimulating its catalytic activity.

  8. Ionic liquids increase the catalytic efficiency of a lipase (Lip1) from an antarctic thermophilic bacterium.

    Science.gov (United States)

    Muñoz, Patricio A; Correa-Llantén, Daniela N; Blamey, Jenny M

    2015-01-01

    Lipases catalyze the hydrolysis and synthesis of triglycerides and their reactions are widely used in industry. The use of ionic liquids has been explored in order to improve their catalytic properties. However, the effect of these compounds on kinetic parameters of lipases has been poorly understood. A study of the kinetic parameters of Lip1, the most thermostable lipase from the supernatant of the strain ID17, a thermophilic bacterium isolated from Deception Island, Antarctica, and a member of the genus Geobacillus is presented. Kinetic parameters of Lip1 were modulated by the use of ionic liquids BmimPF6 and BmimBF4. The maximum reaction rate of Lip1 was improved in the presence of both salts. The highest effect was observed when BmimPF6 was added in the reaction mix, resulting in a higher hydrolytic activity and in a modulation of the catalytic efficiency of the enzyme. However, the catalytic efficiency did not change in the presence of BmimBF4. The increase of the reaction rates of Lip1 promoted by these ionic liquids could be related to possible changes in the Lip1 structure. This effect was measured by quenching of tryptophan fluorescence of the enzyme, when it was incubated with each liquid salt. In conclusion, the hydrolytic activity of Lip1 is modulated by the ionic liquids BmimBF4 and BmimPF6, improving the reaction rate and the catalytic efficiency of this enzyme when BmimPF6 was used. This effect is probably due to changes in the structure of Lip1 induced by the presence of these ionic liquids, stimulating its catalytic activity. PMID:25425150

  9. Subcutaneous Adipose Tissue Transplantation in Diet-Induced Obese Mice Attenuates Metabolic Dysregulation While Removal Exacerbates It.

    Science.gov (United States)

    Foster, M T; Softic, S; Caldwell, J; Kohli, R; de Kloet, A D; Seeley, R J

    2013-08-01

    Adipose tissue distribution is an important determinant of obesity-related comorbidities. It is well established that central obesity (visceral adipose tissue accumulation) is a risk factor for many adverse health consequences such as dyslipidemia, insulin resistance and type-2-diabetes. We hypothesize that the metabolic dysregulation that occurs following high fat diet-induced increases in adiposity are due to alterations in visceral adipose tissue function which influence lipid flux to the liver via the portal vein. This metabolic pathology is not exclusively due to increases in visceral adipose tissue mass but also driven by intrinsic characteristics of this particular depot. In Experiment 1, high fat diet (HFD)-induced obese control (abdominal incision, but no fat manipulation) or autologous (excision and subsequent relocation of adipose tissue) subcutaneous tissue transplantation to the visceral cavity. In Experiment 2 mice received control surgery, subcutaneous fat removal or hetero-transplantation (tissue from obese donor) to the visceral cavity. Body composition analysis and glucose tolerance tests were performed 4 weeks post-surgery. Adipose mass and portal adipokines, cytokines, lipids and insulin were measured from samples collected at 5 weeks post-surgery. Auto- and hetero- transplantation in obese mice improved glucose tolerance, decreased systemic insulin concentration and reduced portal lipids and hepatic triglycerides compared with HFD controls. Hetero-transplantation of subcutaneous adipose tissue to the visceral cavity in obese mice restored hepatic insulin sensitivity and reduced insulin and leptin concentrations to chow control levels. Fat removal, however, as an independent procedure exacerbated obesity-induced increases in leptin and insulin concentrations. Overall subcutaneous adipose tissue protects against aspects of metabolic dysregulation in obese mice. Transplantation-induced improvements do not occur via enhanced storage of lipid in

  10. Activities of asymmetric dimethylarginine-related enzymes in white adipose tissue are associated with circulating lipid biomarkers

    Directory of Open Access Journals (Sweden)

    Iwasaki Hiroaki

    2012-04-01

    Full Text Available Abstract Background Asymmetric NG,NG-dimethylarginine (ADMA, an endogenous inhibitor of nitric oxide synthase, is regulated by the enzymatic participants of synthetic and metabolic processes, i.e., type I protein N-arginine methyltransferase (PRMT and dimethylarginine dimethylaminohydrolase (DDAH. Previous reports have demonstrated that circulating ADMA levels can vary in patients with type 1 and type 2 diabetes mellitus (T2DM. White adipose tissue expresses the full enzymatic machinery necessary for ADMA production and metabolism; however, modulation of the activities of adipose ADMA-related enzymes in T2DM remains to be determined. Methods A rodent model of T2DM using 11- and 20-week old Goto-Kakizaki (GK rats was used. The expression and catalytic activity of PRMT1 and DDAH1 and 2 in the white adipose tissues (periepididymal, visceral and subcutaneous fats and femur skeletal muscle tissue were determined by immunoblotting, in vitro methyltransferase and in vitro citrulline assays. Results Non-obese diabetic GK rats showed low expression and activity of adipose PRMT1 compared to age-matched Wistar controls. Adipose tissues from the periepididymal, visceral and subcutaneous fats of GK rats had high DDAH1 expression and total DDAH activity, whereas the DDAH2 expression was lowered below the control value. This dynamic of ADMA-related enzymes in white adipose tissues was distinct from that of skeletal muscle tissue. GK rats had lower levels of serum non-esterified fatty acids (NEFA and triglycerides (TG than the control rats. In all subjects the adipose PRMT1 and DDAH activities were statistically correlated with the levels of serum NEFA and TG. Conclusion Activities of PRMT1 and DDAH in white adipose tissues were altered in diabetic GK rats in an organ-specific manner, which was reflected in the serum levels of NEFA and TG. Changes in adipose ADMA-related enzymes might play a part in the function of white adipose tissue.

  11. [Residual risk: The roles of triglycerides and high density lipoproteins].

    Science.gov (United States)

    Grammer, Tanja; Kleber, Marcus; Silbernagel, Günther; Scharnagl, Hubert; März, Winfried

    2016-06-01

    In clinical trials, the reduction of LDL-cholesterol (LDL-C) with statins reduces the incidence rate of cardiovascular events by approximately one third. This means, that a sizeable "residual risk" remains. Besides high lipoprotein (a), disorders in the metabolism of triglyceride-rich lipoproteins and high density liproteins have been implicated as effectors of the residual risk. Both lipoprotein parameters correlate inversely with each other. Therefore, the etiological contributions of triglycerides and / or of HDL for developing cardiovascular disease can hardly be estimated from either observational studies or from intervention studies. The largely disappointing results of intervention studies with inhibitors of the cholesteryl ester transfer protein and in particular the available set of genetically-epidemiological studies suggest that in the last decade, the importance of HDL cholesterol has been overvalued, while the importance of triglycerides has been underestimated. High triglycerides not always atherogenic, but only if they are associated with the accumulation relatively cholesterol-enriched, incompletely catabolized remnants of chylomicrons and very low density lipoproteins (familial type III hyperlipidemia, metabolic syndrome, diabetes mellitus). The normalization of the concentration of triglycerides and remnants by inhibiting the expression of apolipoprotein C3 is hence a new, promising therapeutic target. PMID:27305303

  12. Lipase as a marker enzyme for bioassays

    International Nuclear Information System (INIS)

    The detection of various biochemical analytes is usually carried out after the biorecognition with labeled molecules. The most common label is still the radioactivity. However, the short half-life and health hazard of the radionuclides make the non-radioactive labels more popular. The fluorescence and chemiluminescence markers allow direct measurements, but they are not as sensitive as the enzymatic labels. Enzyme labels are the most sensitive non-radioactive markers and in combination with suitable colorimetric or chemiluminescence substrates the same detection limits as with radioactivity can be achieved. Direct enzyme markers offer not only a high sensitivity, but also a low background and non problematic and fast detection. The most commonly used enzymatic labels are horse-radish peroxidase and the alkaline phosphatase. In this work a new enzymatic label, lipase from Candida rugosa, was introduced. This 60 kDa large protein from the group of hydrolases is more active then the commercially available enzymes. In this thesis the most important characteristics of the lipase were characterized: specific activity, substrate specificity, temperature stability, pH optimum, storage stability and influence of detergents an the protein. The lipase was used for the labeling of short oligonucleotides (20-30 nucleotides long). The labeling was carried out through a terminal pending reactive group not to prevent the formation of hybrids during the hybridization process. The hybridization with labeled oligonucleotides is a fast process in comparison to the hybridization with long nucleic acids. This process takes place in simple working solutions at relatively low temperatures. Under these condition lipase remains active and stable, which leads to high signals. According to the high stability of lipase under working conditions, wide pH optimum and extreme high specific activity in comparison to the commonly used enzyme labels make it possible to open new perspectives for

  13. Genomic determinants of triglyceride and cholesterol distribution into lipoprotein fractions in the rat.

    Directory of Open Access Journals (Sweden)

    Miloslava Hodúlová

    Full Text Available The plasma profile of major lipoprotein classes and its subdivision into particular fractions plays a crucial role in the pathogenesis of atherosclerosis and is a major predictor of coronary artery disease. Our aim was to identify genomic determinants of triglyceride and cholesterol distribution into lipoprotein fractions and lipoprotein particle sizes in the recombinant inbred rat set PXO, in which alleles of two rat models of the metabolic syndrome (SHR and PD inbred strains segregate together with those from Brown Norway rat strain. Adult male rats of 15 PXO strains (n = 8-13/strain and two progenitor strains SHR-Lx (n = 13 and BXH2/Cub (n = 18 were subjected to one-week of high-sucrose diet feeding. We performed association analyses of triglyceride (TG and cholesterol (C concentrations in 20 lipoprotein fractions and the size of major classes of lipoprotein particles utilizing 704 polymorphic microsatellite markers, the genome-wide significance was validated by 2,000 permutations per trait. Subsequent in silico focusing of the identified quantitative trait loci was completed using a map of over 20,000 single nucleotide polymorphisms. In most of the phenotypes we identified substantial gradient among the strains (e.g. VLDL-TG from 5.6 to 66.7 mg/dl. We have identified 14 loci (encompassing 1 to 65 genes on rat chromosomes 3, 4, 7, 8, 11 and 12 showing suggestive or significant association to one or more of the studied traits. PXO strains carrying the SHR allele displayed significantly higher values of the linked traits except for LDL-TG and adiposity index. Cholesterol concentrations in large, medium and very small LDL particles were significantly associated to a haplotype block spanning part of a single gene, low density lipoprotein receptor-related protein 1B (Lrp1b. Using genome-wide association we have identified new genetic determinants of triglyceride and cholesterol distribution into lipoprotein fractions in the recombinant

  14. Efficient biocatalyst by encapsulating lipase into nanoporous gold

    Science.gov (United States)

    Du, Xiaoyu; Liu, Xueying; Li, Yufei; Wu, Chao; Wang, Xia; Xu, Ping

    2013-04-01

    Lipases are one of the most important biocatalysts for biotechnological applications. Immobilization is an efficient method to increase the stability and reusability of lipases. In this study, nanoporous gold (NPG), a new kind of nanoporous material with tunable porosity and excellent biocompatibility, was employed as an effective support for lipase immobilization. The pore size of NPG and adsorption time played key roles in the construction of lipase-NPG biocomposites. The morphology and composition of NPG before and after lipase loading are verified using a scanning electron microscope, equipped with an energy-dispersive X-ray spectrometer. The resulting lipase-NPG biocomposites exhibited excellent catalytic activity and remarkable reusability. The catalytic activity of the lipase-NPG biocomposite with a pore size of 35 nm had no decrease after ten recycles. Besides, the lipase-NPG biocomposite exhibited high catalytic activity in a broader pH range and higher temperature than that of free lipase. In addition, the leaching of lipase from NPG could be prevented by matching the protein's diameter and pore size. Thus, the encapsulation of enzymes within NPG is quite useful for establishing new functions and will have wide applications for different chemical processes.

  15. Lipoprotein lipase activity and mass, apolipoprotein C-II mass and polymorphisms of apolipoproteins E and A5 in subjects with prior acute hypertriglyceridaemic pancreatitis

    Directory of Open Access Journals (Sweden)

    García-Arias Carlota

    2009-06-01

    Full Text Available Abstract Background Severe hypertriglyceridaemia due to chylomicronemia may trigger an acute pancreatitis. However, the basic underlying mechanism is usually not well understood. We decided to analyze some proteins involved in the catabolism of triglyceride-rich lipoproteins in patients with severe hypertriglyceridaemia. Methods Twenty-four survivors of acute hypertriglyceridaemic pancreatitis (cases and 31 patients with severe hypertriglyceridaemia (controls were included. Clinical and anthropometrical data, chylomicronaemia, lipoprotein profile, postheparin lipoprotein lipase mass and activity, hepatic lipase activity, apolipoprotein C II and CIII mass, apo E and A5 polymorphisms were assessed. Results Only five cases were found to have LPL mass and activity deficiency, all of them thin and having the first episode in childhood. No cases had apolipoprotein CII deficiency. No significant differences were found between the non-deficient LPL cases and the controls in terms of obesity, diabetes, alcohol consumption, drug therapy, gender distribution, evidence of fasting chylomicronaemia, lipid levels, LPL activity and mass, hepatic lipase activity, CII and CIII mass or apo E polymorphisms. However, the SNP S19W of apo A5 tended to be more prevalent in cases than controls (40% vs. 23%, NS. Conclusion Primary defects in LPL and C-II are rare in survivors of acute hypertriglyceridaemic pancreatitis; lipase activity measurements should be restricted to those having their first episode during chilhood.

  16. Concentration, partial characterization, and immobilization of lipase extract from P. brevicompactum by solid-state fermentation of babassu cake and castor bean cake.

    Science.gov (United States)

    Silva, Marceli Fernandes; Freire, Denise M G; de Castro, Aline Machado; Di Luccio, Marco; Mazutti, Marcio A; Oliveira, J Vladimir; Treichel, Helen; de Oliveira, Débora

    2011-07-01

    One relevant limitation hindering the industrial application of microbial lipases has been attributed to their production cost, which is determined by the production yield, enzyme stability among other. The objective of this work was to evaluate the concentration and immobilization of lipase extracts from Penicillium brevicompactum obtained by solid-state fermentation of babassu cake and castor bean cake. The precipitation with ammonium sulfate 60% of saturation of crude extract obtained with babassu cake as raw material showed an enhancement in hydrolytic and esterification activities from 31.82 to 227.57 U/g and from 170.92 to 207.40 U/g, respectively. Concentrated lipase extracts showed preference to medium-chain triglycerides and fatty acids. It is shown that the enzyme activity is maintained during storage at low temperatures (4 and -10°C) for up to 30 days. Higher esterification activities were achieved when the lipase extract was immobilized in sodium alginate and activated coal. PMID:21258873

  17. QCM-D and ToF-SIMS Investigation to Deconvolute the Relationship between Lipid Adsorption and Orientation on Lipase Activity.

    Science.gov (United States)

    Joyce, Paul; Kempson, Ivan; Prestidge, Clive A

    2015-09-22

    Quartz crystal microbalance with dissipation (QCM-D) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were used to provide insights into the relationship between lipid adsorption kinetics and molecular behavior in porous silica particles of varying hydrophobicities on lipase activity. Lipase (an interfacial enzyme that cleaves ester bonds to break down lipids to fatty acids and monoglycerides) activity was controlled by loading triglycerides at different surface coverages in hydrophilic and hydrophobic porous silica particles. The rate of lipid adsorption increased 2-fold for the hydrophobic surface compared to the hydrophilic surface. However, for submonolayer lipid coverage, the hydrophilic surface enhanced lipase activity 4-fold, whereas the hydrophobic surface inhibited lipase activity 16-fold, compared to lipid droplets in water. A difference in lipid orientation for low surface coverage, evidenced by ToF-SIMS, indicated that lipid adsorbs to hydrophilic silica in a conformation promoting hydrolysis. Multilayer coverage on hydrophobic and hydrophilic surfaces was indistinguishable with ToF-SIMS analysis. Increased lipid adsorption for both substrates facilitated digestion kinetics comparable to a conventional emulsion. Improved understanding of the interfacial adsorption and orientation of lipid and its digestibility in porous silica has implications in improving the uptake of pharmaceuticals and nutrients from lipid-based delivery systems. PMID:26340506

  18. LXR activation by GW3965 alters fat tissue distribution and adipose tissue inflammation in ob/ob female mice[S

    OpenAIRE

    Archer, Amena; Stolarczyk, Émilie; Doria, Maria Luisa; Helguero, Luisa; Domingues, Rosário; Howard, Jane K; Mode, Agneta; Korach-André, Marion; Gustafsson, Jan-Åke

    2013-01-01

    To investigate the role of liver X receptor (LXR) in adipose tissue metabolism during obesity, ob/ob mice were treated for 5 weeks with the synthetic LXR agonist GW3965. MRI analysis revealed that pharmacological activation of LXR modified fat distribution by decreasing visceral (VS) fat and inversely increasing subcutaneous (SC) fat storage without affecting whole body fat content. This was concordant with opposite regulation by GW3965 of the lipolytic markers hormone-sensitive lipase (HSL) ...

  19. Sleep deprivation affects inflammatory marker expression in adipose tissue

    Directory of Open Access Journals (Sweden)

    Santos Ronaldo VT

    2010-10-01

    Full Text Available Abstract Sleep deprivation has been shown to increase inflammatory markers in rat sera and peripheral blood mononuclear cells. Inflammation is a condition associated with pathologies such as obesity, cancer, and cardiovascular diseases. We investigated changes in the pro and anti-inflammatory cytokines and adipokines in different depots of white adipose tissue in rats. We also assessed lipid profiles and serum levels of corticosterone, leptin, and adiponectin after 96 hours of sleep deprivation. Methods The study consisted of two groups: a control (C group and a paradoxical sleep deprivation by 96 h (PSD group. Ten rats were randomly assigned to either the control group (C or the PSD. Mesenteric (MEAT and retroperitoneal (RPAT adipose tissue, liver and serum were collected following completion of the PSD protocol. Levels of interleukin (IL-6, interleukin (IL-10 and tumour necrosis factor (TNF-α were analysed in MEAT and RPAT, and leptin, adiponectin, glucose, corticosterone and lipid profile levels were analysed in serum. Results IL-6 levels were elevated in RPAT but remained unchanged in MEAT after PSD. IL-10 protein concentration was not altered in either depot, and TNF-α levels decreased in MEAT. Glucose, triglycerides (TG, VLDL and leptin decreased in serum after 96 hours of PSD; adiponectin was not altered and corticosterone was increased. Conclusion PSD decreased fat mass and may modulate the cytokine content in different depots of adipose tissue. The inflammatory response was diminished in both depots of adipose tissue, with increased IL-6 levels in RPAT and decreased TNF-α protein concentrations in MEAT and increased levels of corticosterone in serum.

  20. In silico and experimental characterization of chimeric Bacillus thermocatenulatus lipase with the complete conserved pentapeptide of Candida rugosa lipase.

    Science.gov (United States)

    Hosseini, Mostafa; Karkhane, Ali Asghar; Yakhchali, Bagher; Shamsara, Mehdi; Aminzadeh, Saeed; Morshedi, Dena; Haghbeen, Kamahldin; Torktaz, Ibrahim; Karimi, Esmat; Safari, Zahra

    2013-02-01

    Lipases are one of the highest value commercial enzymes as they have broad applications in detergent, food, pharmaceutical, and dairy industries. To provide chimeric Bacillus thermocatenulatus lipase (BTL2), the completely conserved pentapeptide (¹¹²Ala-His-Ser-Gln-Gly¹¹⁶) was replaced with similar sequences (²⁰⁷Gly-Glu-Ser-Ala-Gly²¹¹) of Candida rugosa lipase (CLR) at the nucleophilic elbow region. For this purpose, three mutations including A112G, H113E, and Q115A were inserted in the conserved pentapeptide sequence of btl2 gene. Based on the crystal structures of 2W22, the best structure of opened form of the chimeric lipases were garnered using the MODELLER v9.10 software. The native and chimeric lipases were docked to a set of ligands, and a trial version of Molegro Virtual Docker (MVD) software was used to obtain the energy values. Docking results confirmed chimeric lipase to be better than the native lipase. Following the in silico study, cloning experiments were conducted and expression of native and chimeric btl2 gene in Pichia pastoris was performed. The native and chimeric lipases were purified, and the effect of these mutations on characteristics of chimeric lipase studied and then compared with those of native lipase. Chimeric lipase exhibited 1.6-fold higher activity than the native lipase at 55 °C. The highest percentage of both lipases activity was observed at 60 °C and pH of 8.0. The ion Ca²⁺ slightly inhibited the activity of both lipases, whereas the organic solvent enhanced the lipase stability of chimeric lipase as compared with the native lipase. According to the results, the presence of two glycine residues at the conserved pentapeptide region of this chimeric lipase (¹¹²Gly-Glu-Ser-Ala-Gly¹¹⁶) may increase the flexibility of the nucleophilic elbow region and affect the enzyme activity level. PMID:23274720

  1. RESEARCH PROGRESS AND APPLICATION FIELDS OF MICROBIAL LIPASE%微生物脂肪酶的应用领域及研究进展

    Institute of Scientific and Technical Information of China (English)

    张开平; 惠明; 田青; 尚小利; 尹向垄

    2012-01-01

    With the development of industrial catalytic technology, lipase as an important biocatalyst has become the research focus all around the world. The paper summarized and prospected the structure and the property of the microbial lipase and the application in the fields of grain, oil and food processing, biodiesel, organic synthesis, chiral synthesis and the triglyceride structure determination.%随着工业催化技术的发展,脂肪酶作为一种重要的生物催化剂现已成为世界研究的热点.对微生物脂肪酶的结构、性质以及在粮油食品加工、生物柴油、有机合成、手性化合物合成及三甘酯结构测定等方面的应用进行了综述和展望.

  2. Immobilization of Yarrowia lipolytica Lipase on Macroporous Resin Using Different Methods: Characterization of the Biocatalysts in Hydrolysis Reaction

    OpenAIRE

    2015-01-01

    To improve the reusability and organic solvent tolerance of microbial lipase and expand the application of lipase (hydrolysis, esterification, and transesterification), we immobilized marine microbial lipase using different methods and determined the properties of immobilized lipases. Considering the activity and cost of immobilized lipase, the concentration of lipase was fixed at 2 mg/mL. The optimal temperature of immobilized lipases was 40°C and 5°C higher than free lipase. The activities ...

  3. Defective differentiation of adipose precursor cells from lipodystrophic mice lacking perilipin 1.

    Directory of Open Access Journals (Sweden)

    Ying Lyu

    Full Text Available Perilipin 1 (Plin1 localizes at the surface of lipid droplets to regulate triglyceride storage and hydrolysis in adipocytes. Plin1 defect leads to low adiposity in mice and partial lipodystrophy in human. This study investigated the roles of Plin1 in adipocyte differentiation. Plin1 null (-/- mice showed plenty of multilocular adipocytes and small unilocular adipocytes in adipose tissue, along with lack of a subpopulation of adipose progenitor cells capable of in vivo adipogenesis and along with downregulation of adipogenic pathway. Before initiation of differentiation, adipose stromal-vascular cells (SVCs from Plin1-/- mice already accumulated numerous tiny lipid droplets, which increased in number and size during the first 12-h induction but thereafter became disappeared at day 1 of differentiation. The adipogenic signaling was dysregulated despite protein level of PPARγ was near normal in Plin1-/- SVCs like in Plin1-/- adipose tissue. Heterozygous Plin1+/- SVCs were able to develop lipid droplets, with both the number and size more than in Plin1-/- SVCs but less than in Plin1+/+ SVCs, indicating that Plin1 haploinsufficiency accounts for attenuated adipogenesis. Aberrant lipid droplet growth and differentiation of Plin1-/- SVCs were rescued by adenoviral Plin1 expression and were ameliorated by enhanced or prolonged adipogenic stimulation. Our finding suggests that Plin1 plays an important role in adipocyte differentiation and provides an insight into the pathology of partial lipodystrophy in patients with Plin1 mutation.

  4. A metabolomic study of adipose tissue in mice with a disruption of the circadian system.

    Science.gov (United States)

    Castro, C; Briggs, W; Paschos, G K; FitzGerald, G A; Griffin, J L

    2015-07-01

    Adipose tissue functions in terms of energy homeostasis as a rheostat for blood triglyceride, regulating its concentration, in response to external stimuli. In addition it acts as a barometer to inform the central nervous system of energy levels which can vary dramatically between meals and according to energy demand. Here a metabolomic approach, combining both Mass Spectrometry and Nuclear Magnetic Resonance spectroscopy, was used to analyse both white and brown adipose tissue in mice with adipocyte-specific deletion of Arntl (also known as Bmal1), a gene encoding a core molecular clock component. The results are consistent with a peripheral circadian clock playing a central role in metabolic regulation of both brown and white adipose tissue in rodents and show that Arntl induced global changes in both tissues which were distinct for the two types. In particular, anterior subcutaneous white adipose tissue (ASWAT) tissue was effected by a reduction in the degree of unsaturation of fatty acids, while brown adipose tissue (BAT) changes were associated with a reduction in chain length. In addition the aqueous fraction of metabolites in BAT were profoundly affected by Arntl disruption, consistent with the dynamic role of this tissue in maintaining body temperature across the day-night cycle and an upregulation in fatty acid oxidation and citric acid cycle activity to generate heat during the day when rats are inactive (increases in 3-hydroxybutyrate and glutamate), and increased synthesis and storage of lipids during the night when rats feed more (increased concentrations of glycerol, choline and glycerophosphocholine).

  5. Development and differentiation of adipose tissue

    OpenAIRE

    Ivković-Lazar Tatjana A.

    2003-01-01

    Introduction For years adipose tissue has been considered inert, serving only as a depot of energy surplus. However, there have been recent changes, undoubtedly due to advancement of methods for studying the morphology and metabolic activities of adipose tissue (microdialysis and adipose tissue catheterization). In normal-weight subjects, adipose tissue makes 10-12% with males and 15-20% with females. About 80 % of adipose tissue is located under the skin, and the rest envelops the internal o...

  6. Gastric lipase: localization of the enzyme in the stomach

    International Nuclear Information System (INIS)

    Isolated gastric glands prepared from human and rabbit stomach secrete lipase in response to secretagogues. They have investigated the localization of this enzyme in three species (rabbit, baboon, guinea pig). Gastric mucosa was sampled from the cardia (C), fundus-smooth (FS), fundus-ruggae (FR) and the antral area (A). Lipase activity was measured in mucosal homogenates using 3H-triolein as substrate and is expressed in units (U) = nmols free fatty acid released/min/mg wet weight. The localization of lipase is compared with that of pepsin (measured by hydrolysis of 2% hemoglobin at pH 1.8 and expressed in I.U.). Lipase is localized in a well defined area in the rabbit and is diffusely distributed in both guinea pig and baboon. The distribution of lipase and pepsin containing cells differs in all three species. The cellular origin of gastric lipase remains to be determined

  7. Dependency of water concentration on ethanolysis of trioleoylglycerol by lipases

    DEFF Research Database (Denmark)

    Piyatheerawong, W.; Iwasaki, Y; Xu, Xuebing;

    2004-01-01

    The effects of water concentration on ethanolysis of trioleoylglycerol catalyzed by four different lipases were studied. The target product of the ethanolysis was 2-monooleoylglycerol (2-MO). Novozym 435 (a commercially available preparation of immobilized Candida antarctica lipase B, CALB......) exhibited both the highest product yield and the reaction rate at very low (less than 1 wt.%) free water concentration. Its catalytic activity did not drop even in dry state, i.e. in the system of dry CALB in dry ethanol (water concentration was ca. 0.1 wt.%). In contrast, other three immobilized lipases...... tested (Rhizomucor miehei lipase, Burkholderia cepacia lipase and Thermomyces lanuginosus lipase) required larger amounts of free water (ca. 7-9 wt.%) for their best performance and exhibited no ethanolysis reaction at low free water concentrations. The CALB's anomalous behavior was also observed...

  8. Screening for lipase activity in the oil palm.

    Science.gov (United States)

    Sambanthamurthi, R; Rajanaidu, N; Hasnah Parman, S

    2000-12-01

    The oil palm mesocarp contains an endogenous lipase which is strongly activated at low temperature. Lipase activity is thus very conveniently assayed by prior exposure of the fruits to low temperature. More than 100 oil palm samples from the germplasm collection of the Palm Oil Research Institute of Malaysia (now known as the Malaysian Palm Oil Board) were screened for non-esterified fatty acid activity using both the low-temperature activation assay and a radioactivity assay. The results showed good correlation between assay procedures. The different samples had a very wide range of lipase activity. Elaeis oleifera samples had significantly lower lipase activity compared with E. guineensis (var. tenera) samples. Even within E. guineensis (var. tenera), there was a wide range of activity. The results confirmed that lipase activity is genotype-dependent. Selection for lipase genotypes is thus possible and this will have obvious commercial value. PMID:11171201

  9. Rat liver contains a limited number of binding sites for hepatic lipase

    OpenAIRE

    Schoonderwoerd, Kees; Verhoeven, Adrie; Jansen, Hans

    1994-01-01

    textabstractThe binding of hepatic lipase to rat liver was studied in an ex vivo perfusion model. The livers were perfused with media containing partially purified rat hepatic lipase or bovine milk lipoprotein lipase. The activity of the enzymes was determined in the perfusion media before and after passage through the liver. During perfusion with a hepatic-lipase-containing medium the lipase activity in the medium did not change, indicating that there was no net binding of lipase by the live...

  10. Molecular characterization of a proteolysis-resistant lipase from Bacillus pumilus SG2

    OpenAIRE

    Sangeetha, R.; Arulpandi, I.; A Geetha

    2014-01-01

    Proteolysis-resistant lipases can be well exploited by industrial processes which employ both lipase and protease as biocatalysts. A proteolysis resistant lipase from Bacillus pumilus SG2 was isolated, purified and characterized earlier. The lipase was resistant to native and commercial proteases. In the present work, we have characterized the lip gene which encodes the proteolysis-resistant lipase from Bacillus pumilus SG2. The parameters and structural details of lipase were analysed. The l...

  11. Effects of Deltamethrin on Lipase Activity in Guppies (Poecilia reticulata)

    OpenAIRE

    Güneş, Elif; Sedat V. Yerli

    2011-01-01

    Effect of the deltamethrin, which is extensively used synthetic pyrethroid, was investigated on the lipase activity of Poecilia reticulata in the present study. One control and five experimental groups were exposed to different concentrations of deltamethrin. Three experiments, including 60 guppies each, were conducted. Titration method was used in order to determine the lipase activity. Lipase activity level in control group was 5 U/min, while it was 2.5 U/min in the highest concentration of...

  12. Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae)

    OpenAIRE

    Seniwati

    2012-01-01

    Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of op...

  13. Expression of the Staphylococcus hyicus Lipase in Lactococcus lactis

    OpenAIRE

    Drouault, Sophie; Corthier, Gerard; Ehrlich, S. Dusko; Renault, Pierre

    2000-01-01

    The extracellular Staphylococcus hyicus lipase was expressed under the control of different promoters in Lactococcus lactis and Bacillus subtilis. Its expression at high and moderate levels is toxic for the former and the latter hosts, respectively. In L. lactis, the lipase was expressed at a high level, up to 30% of the total cellular proteins, under the control of the inducible promoter PnisA. About 80% of the lipase remained associated with the cells. Close to half of this amount remained ...

  14. Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae)

    OpenAIRE

    Seniwati Dali; A. B. D. Rauf Patong; M.Noor Jalaluddin; Pirman; Baharuddin Hamzah

    2011-01-01

    Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of optimum pH, optimum ...

  15. Studies on the incorporation of lipase in synthetic polymerisable vesicles.

    OpenAIRE

    Mosmuller, E.W.J.

    1993-01-01

    This thesis describes studies on the suitability of synthetic polymerisable vesicles for the incorporation and stabilisation of lipase for the bioconversion of organic chemical compounds.In chapter 1 , some characteristics are reviewed of hydrolytic enzymes, and more specific those of lipases. In chapter 2 an overview is presented of the features and properties of surfactants and vesicles.In chapter 3 , the incorporation is described of lipase from Candida cylindracea (CCL) into polymerisable...

  16. The use of medium-chain triglycerides in preterm infants

    NARCIS (Netherlands)

    E.J. Sulkers (Eric)

    1993-01-01

    textabstractFor many years, medium-chain triglycerides (MCTs), with a chain length of eight and ten carbon atoms, have been included in preterm infant formulas. MCTs are manufactured by reesterification of medium-chain fatty acids (MCFAs) from coconut oil, and their intestil1al absorption is assumed

  17. Fatty liver and medium chain triglyceride (MCT) diet.

    OpenAIRE

    Beverley, D; Arthur, R.

    1988-01-01

    A 12 year old boy with intractable epilepsy developed fatty infiltration of the liver after three years' treatment on the medium chain triglyceride (MCT) diet. This was not associated with any hepatic dysfunction and resolved after discontinuing the diet. Three of four other patients on the same diet had evidence of hepatic steatosis.

  18. Diagnostic value of postprandial triglyceride testing in healthy subjects

    DEFF Research Database (Denmark)

    Mihas, Constantinos; Kolovou, Genovefa D; Mikhailidis, Dimitri P;

    2011-01-01

    Triglycerides (TGs) are measured in studies evaluating changes in non-fasting lipid profiles after a fat tolerance test (FTT); however, the optimal timing for TG measurements after the oral fat load is unclear. The aim of this study was to evaluate how non-fasting TG levels vary after an oral FTT...

  19. Myocardial triglycerides : magnetic resonance spectroscopy in health and diabetes

    NARCIS (Netherlands)

    Hammer, Sebastiaan

    2008-01-01

    In this thesis we focused on the functional and metabolic consequences of myocardial triglyceride (TG) accumulation in healthy subjects and in patients with diabetes mellitus. Ectopic accumulation of TGs is associated with organ dysfunction in metabolic disease in experimental animal studies. These

  20. Lipase Activity among Bacteria Isolated from Amazonian Soils

    OpenAIRE

    André Luis Willerding; Luiz Antonio de Oliveira; Francisco Wesen Moreira; Mariana Gomes Germano; Aloísio Freitas Chagas

    2011-01-01

    The objective of this study was to select lipase-producing bacteria collected from different counties of the Amazon region. Of the 440 bacteria strains, 181 were selected for the lipase assay in qualitative tests at Petri dishes, being 75 (41%) lipase positive. The enzymatic index was determined during fifteen days at different temperatures (30°, 35°, 40°, and 45°C). The highest lipase activity was observed within 72 hours at 30°C. Twelve bacteria strains presented an index equal to or greate...

  1. Covalent functionalization of multi-walled carbon nanotubes by lipase

    International Nuclear Information System (INIS)

    Lipase from Candida rugosa was covalently anchored onto acid-treated multi-walled carbon nanotubes (MWNTs) through a self-catalytic mechanism. A variety of characterization techniques including FTIR, Raman spectroscopy, and XPS were employed to demonstrate the formation of the ester linkage between lipase and MWNTs. The MWNTs-lipase biocomposites showed significantly increased solubility in some common-used organic solvents, such as THF, DMF and chloroform. This study may offer a novel and facile route for covalent modification of carbon nanotubes, and expand the potential utilization of both lipases and MWNTs in the fields of biocatalyst and biosensor

  2. The value of immunoreactive lipase in acute pancreatitis.

    OpenAIRE

    1988-01-01

    We have evaluated a new agglutination test for serum immunoreactive lipase in 24 patients with abdominal pain and hyperamylasaemia. On admission all 20 patients with acute pancreatitis had a positive lipase test, 3 of the 4 patients who did not have pancreatitis had a negative lipase test. The sensitivity of the lipase test on day 1 is 100%, the specificity 96% and predictive value of a positive test is 95.2% compared to 83% for amylase. A negative test excludes pancreatitis. In addition, the...

  3. Applications of immobilized Thermomyces lanuginosa lipase in interesterification

    DEFF Research Database (Denmark)

    Yang, Tiankui; Fruekilde, Maj-Britt; Xu, Xuebing

    2003-01-01

    (RSM). Thermomyces lanuginosa lipase had an activity similar to that of immobilized Rhizomucor miehei lipase (Lipozyme RM IM) in the glycerolysis of sunflower oil, but the former had higher activity at a low reaction temperature (5degreesC). Thermomyces lanuginosa lipase was found to have much lower...... catalytic activity than Lipozyme RM IM in the acidolysis of sunflower oil with caprylic acid. However, the activity of T. lanuginosa lipase was only slightly lower than that of Lipozyme RM IM in the ester-ester exchange between tripalmitin (PPP) and the ethyl esters of EPA and DHA (EE). For this reason...

  4. Computational Modeling of the Electrochemical System of Lipase Activity Detection

    Directory of Open Access Journals (Sweden)

    Valdemaras Razumas

    2008-06-01

    Full Text Available This paper presents computational modeling of response kinetics of bioelectroanalytical system based on solid supported lipase substrate and lipase interaction. The model assumes that lipase substrate is formed by dripping and drying a small amount of the ethanol solution of 9-(5’-ferrocenylpentanoyloxynonyl disulfide (FPONDS and that lipase is capable of cleaving FPONDS ester bonds via hydrolysis mechanism. Two mathematical models have been developed and evaluated trough computational simulation series by comparing them to experimental data. The results of simulation demonstrate that a good fitting might be obtained only taking into account non-linear substrate wash off process.

  5. Seed lipases: sources, applications and properties - a review

    Directory of Open Access Journals (Sweden)

    M. Barros

    2010-03-01

    Full Text Available This paper provides an overview regarding the main aspects of seed lipases, such as the reactions catalyzed, physiological functions, specificities, sources and applications. Lipases are ubiquitous in nature and are produced by several plants, animals and microorganisms. These enzymes exhibit several very interesting features, such as low cost and easy purification, which make their commercial exploitation as industrial enzymes a potentially attractive alternative. The applications of lipases in food, detergents, oils and fats, medicines and fine chemistry, effluent treatment, biodiesel production and in the cellulose pulp industry, as well as the main sources of oilseed and cereal seed lipases, are reviewed.

  6. Immobilization of Lipase by Covalent Binding on Crosslinked Ally Dextran

    Institute of Scientific and Technical Information of China (English)

    WangChen; SongGuoqiang; 等

    1998-01-01

    Lipase was immobilized by covalent binding on crosslinked allyl dextran using SESA as coupling agent.It is shown that this immobilization approach is an efficient one for lipase.The activity of the immobilized lipase can reach to 300-450U/g(dry weight).It exhibits good temperature stability,can retain 88% activity after being incubated at 70℃ for 2h.Special effects will be expected from our immobilized lipase in its applications in organic media due to the nature of the support.

  7. Release of endothelial cell lipoprotein lipase by plasma lipoproteins and free fatty acids

    International Nuclear Information System (INIS)

    Lipoprotein lipase (LPL) bound to the lumenal surface of vascular endothelial cells is responsible for the hydrolysis of triglycerides in plasma lipoproteins. Studies were performed to investigate whether human plasma lipoproteins and/or free fatty acids would release LPL which was bound to endothelial cells. Purified bovine milk LPL was incubated with cultured porcine aortic endothelial cells resulting in the association of enzyme activity with the cells. When the cells were then incubated with media containing chylomicrons or very low density lipoproteins (VLDL), a concentration-dependent decrease in the cell-associated LPL enzymatic activity was observed. In contrast, incubation with media containing low density lipoproteins or high density lipoproteins produced a much smaller decrease in the cell-associated enzymatic activity. The addition of increasing molar ratios of oleic acid:bovine serum albumin to the media also reduced enzyme activity associated with the endothelial cells. To determine whether the decrease in LPL activity was due to release of the enzyme from the cells or inactivation of the enzyme, studies were performed utilizing radioiodinated bovine LPL. Radiolabeled LPL protein was released from endothelial cells by chylomicrons, VLDL, and by free fatty acids (i.e. oleic acid bound to bovine serum albumin). The release of radiolabeled LPL by VLDL correlated with the generation of free fatty acids from the hydrolysis of VLDL triglyceride by LPL bound to the cells. Inhibition of LPL enzymatic activity by use of a specific monoclonal antibody, reduced the extent of release of 125I-LPL from the endothelial cells by the added VLDL. These results demonstrated that LPL enzymatic activity and protein were removed from endothelial cells by triglyceride-rich lipoproteins (chylomicrons and VLDL) and oleic acid

  8. Hormone-sensitive lipase (HSL) is also a retinyl ester hydrolase: evidence from mice lacking HSL.

    Science.gov (United States)

    Ström, Kristoffer; Gundersen, Thomas E; Hansson, Ola; Lucas, Stéphanie; Fernandez, Céline; Blomhoff, Rune; Holm, Cecilia

    2009-07-01

    Here, we investigated the importance of hormone-sensitive lipase (HSL) as a retinyl ester hydrolase (REH). REH activity was measured in vitro using recombinant HSL and retinyl palmitate. The expression of retinoic acid (RA)-regulated genes and retinoid metabolites were measured in high-fat diet fed HSL-null mice using real-time quantitative PCR and triple-stage liquid chromatography/tandem mass spectrometry, respectively. Age- and gender-matched wild-type littermates were used as controls. The REH activity of rat HSL was found to be higher than that against the hitherto best known HSL substrate, i.e., diacylglycerols. REH activity in white adipose tissue (WAT) of HSL-null mice was completely blunted and accompanied by increased levels of retinyl esters and decreased levels of retinol, retinaldehyde and all-trans RA. Accordingly, genes known to be positively regulated by RA were down-regulated in HSL-null mice, including pRb and RIP140, key factors promoting differentiation into the white over the brown adipocyte lineage. Dietary RA supplementation partly restored WAT mass and the expression of RA-regulated genes in WAT of HSL-null mice. These findings demonstrate the importance of HSL as an REH of adipose tissue and suggest that HSL via this action provides RA and other retinoids for signaling events that are crucial for adipocyte differentiation and lineage commitment.

  9. Lipoprotein lipase deficiency with visceral xanthomas

    Energy Technology Data Exchange (ETDEWEB)

    Servaes, Sabah; Bellah, Richard [Department of Radiology, Philadelphia, PA (United States); Verma, Ritu [Department of Gastroenterology, Philadelphia, PA (United States); Pawel, Bruce [Department of Pathology, Philadelphia, PA (United States)

    2010-08-15

    Lipoprotein lipase deficiency (LLD) is a rare metabolic disorder that typically presents with skin xanthomas and pancreatitis in childhood. We report a case of LLD in an infant who presented with jaundice caused by a pancreatic head mass. Abdominal imaging also incidentally revealed hyperechoic renal masses caused by renal xanthomas. This appearance of the multiple abdominal masses makes this a unique infantile presentation of LLD. (orig.)

  10. Red algae (Gelidium amansii reduces adiposity via activation of lipolysis in rats with diabetes induced by streptozotocin-nicotinamide

    Directory of Open Access Journals (Sweden)

    Tsung-Han Yang

    2015-12-01

    Full Text Available Gelidium amansii (GA is an edible red algae that is distributed mainly in northeastern Taiwan. This study was designed to investigate the effects of GA on plasma glucose, lipids, and adipocytokines in rats with streptozotocin-nicotinamide-induced diabetes. Rats were divided into four groups: (1 rats without diabetes fed a high-fat diet (control group; (2 rats with diabetes fed a high-fat diet; (3 rats with diabetes fed a high-fat diet with thiazolidinedione in the diet; and (4 rats with diabetes fed a high-fat diet and GA. The experimental diet and drinking water were available ad libitum for 11 weeks. After the 11-week feeding study, plasma glucose, triglyceride, and cholesterol concentrations were lower in rats with diabetes fed the GA diet than in animals with diabetes fed the control diet. In addition, cholesterol and triglyceride excretion were significantly higher in rats with diabetes fed the GA diet. Moreover, GA feeding induced lipolysis in both paraepididymal and perirenal adipose tissues. Adipose tissue (paraepididymal and perirenal weight and triglyceride contents were lower after GA treatment. Plasma adipocytokines including tumor necrosis factor-alpha, interleukin-6, and plasminogen activator inhibitor-1 were reduced by GA feeding in rats with diabetes. The results of the current study suggest that GA feeding may regulate plasma glucose and lipid levels and prevent adipose tissue accumulation in rats with diabetes.

  11. Associations of Lipoprotein Lipase Gene rs326 with Changes of Lipid Profiles after a High-Carbohydrate and Low-Fat Diet in Healthy Chinese Han Youth

    OpenAIRE

    Xing-chun Zhu; Jia Lin; Qian Wang; Hui Liu; Li Qiu; Ding-zhi Fang

    2014-01-01

    To investigate the effects of a high-carbohydrate and low-fat (HC/LF) diet on plasma lipids and apolipoproteins (Apos) of healthy Chinese Han youth with different genotypes of lipoprotein lipase gene (LPL) rs326, 56 subjects were given a washout diet of 30.1% fat and 54.1% carbohydrate for seven days, followed by the HC/LF diet of 13.8% fat and 70.1% carbohydrate for six days, with no total energy restriction. Plasma glucose, triglyceride (TG), total cholesterol (TC), high density lipoprotein...

  12. Adipogenic differentiation state-specific gene expression as related to bovine carcass adiposity.

    Science.gov (United States)

    Pickworth, C L; Loerch, S C; Velleman, S G; Pate, J L; Poole, D H; Fluharty, F L

    2011-02-01

    Genetic regulation of the site of fat deposition is not well defined. The objective of this study was to investigate adipogenic differentiation state-specific gene expression in feedlot cattle (>75% Angus; Simmental parentage) of varying adipose accretion patterns. Four groups of 4 steers were selected via ultrasound for the following adipose tissue characteristics: low subcutaneous-low intramuscular (LSQ-LIM), low subcutaneous-high intramuscular (LSQ-HIM), high subcutaneous-low intramuscular (HSQ-LIM), and high subcutaneous-high intramuscular (HSQ-HIM). Adipose tissue from the subcutaneous (SQ) and intramuscular (IM) depots was collected at slaughter. The relative expression of adipogenic genes was evaluated using quantitative PCR. Data were analyzed using the mixed model of SAS, and gene expression data were analyzed using covariate analysis with ribosomal protein L19 as the covariate. No interactions (P > 0.10) were observed between IM and SQ adipose tissue depots for any of the variables measured. Therefore, only the main effects of high and low accretion within a depot and the effects of depot are reported. Steers with LIM had smaller mean diameter IM adipocytes (P 0.10) in any of the genes measured due to high or low adipose accretion. Preadipogenic delta-like kinase1 mRNA was greater in the IM than the SQ adipose tissue; conversely, differentiating and adipogenic genes, lipoprotein lipase, PPARγ, fatty acid synthetase, and fatty acid binding protein 4 were greater (P < 0.001) in the SQ than the IM depot. Intramuscular adipocytes were smaller than SQ adipocytes and had greater expression of the preadipogenic gene, indicating that more hyperplasia was occurring. Meanwhile, SQ adipose tissue contained much larger (P < 0.001) adipocytes that had a greater expression (P < 0.001) of differentiating and adipogenic genes than did the IM adipose tissue, indicating more cells were undergoing differentiation and hypertrophy. Adipogenic differentiation state

  13. Apolipoproteins C-I and C-III Inhibit Lipoprotein Lipase Activity by Displacement of the Enzyme from Lipid Droplets*

    Science.gov (United States)

    Larsson, Mikael; Vorrsjö, Evelina; Talmud, Philippa; Lookene, Aivar; Olivecrona, Gunilla

    2013-01-01

    Apolipoproteins (apo) C-I and C-III are known to inhibit lipoprotein lipase (LPL) activity, but the molecular mechanisms for this remain obscure. We present evidence that either apoC-I or apoC-III, when bound to triglyceride-rich lipoproteins, prevent binding of LPL to the lipid/water interface. This results in decreased lipolytic activity of the enzyme. Site-directed mutagenesis revealed that hydrophobic amino acid residues centrally located in the apoC-III molecule are critical for attachment to lipid emulsion particles and consequently inhibition of LPL activity. Triglyceride-rich lipoproteins stabilize LPL and protect the enzyme from inactivating factors such as angiopoietin-like protein 4 (angptl4). The addition of either apoC-I or apoC-III to triglyceride-rich particles severely diminished their protective effect on LPL and rendered the enzyme more susceptible to inactivation by angptl4. These observations were seen using chylomicrons as well as the synthetic lipid emulsion Intralipid. In the presence of the LPL activator protein apoC-II, more of apoC-I or apoC-III was needed for displacement of LPL from the lipid/water interface. In conclusion, we show that apoC-I and apoC-III inhibit lipolysis by displacing LPL from lipid emulsion particles. We also propose a role for these apolipoproteins in the irreversible inactivation of LPL by factors such as angptl4. PMID:24121499

  14. Apolipoproteins C-I and C-III inhibit lipoprotein lipase activity by displacement of the enzyme from lipid droplets.

    Science.gov (United States)

    Larsson, Mikael; Vorrsjö, Evelina; Talmud, Philippa; Lookene, Aivar; Olivecrona, Gunilla

    2013-11-22

    Apolipoproteins (apo) C-I and C-III are known to inhibit lipoprotein lipase (LPL) activity, but the molecular mechanisms for this remain obscure. We present evidence that either apoC-I or apoC-III, when bound to triglyceride-rich lipoproteins, prevent binding of LPL to the lipid/water interface. This results in decreased lipolytic activity of the enzyme. Site-directed mutagenesis revealed that hydrophobic amino acid residues centrally located in the apoC-III molecule are critical for attachment to lipid emulsion particles and consequently inhibition of LPL activity. Triglyceride-rich lipoproteins stabilize LPL and protect the enzyme from inactivating factors such as angiopoietin-like protein 4 (angptl4). The addition of either apoC-I or apoC-III to triglyceride-rich particles severely diminished their protective effect on LPL and rendered the enzyme more susceptible to inactivation by angptl4. These observations were seen using chylomicrons as well as the synthetic lipid emulsion Intralipid. In the presence of the LPL activator protein apoC-II, more of apoC-I or apoC-III was needed for displacement of LPL from the lipid/water interface. In conclusion, we show that apoC-I and apoC-III inhibit lipolysis by displacing LPL from lipid emulsion particles. We also propose a role for these apolipoproteins in the irreversible inactivation of LPL by factors such as angptl4. PMID:24121499

  15. Alkaline lipase of glyoxysomes is a glycoprotein

    International Nuclear Information System (INIS)

    In castor bean endosperm, the glyoxysomal alkaline lipase is an intrinsic membrane protein. At four days post-germination, the enzyme is also present in the endoplasmic reticulum where it accounts for approximately 15% of total activity. The active enzyme was purified by Maeshima and Beevers from isolated glyoxysomes. Specific antibodies to the 62 kD subunit were raised in rabbits. The anti-lipase has been used in preliminary experiments to determine the relationship between the lipase of the glyoxysomal membrane and the ER. Results indicate the presence of 3 cross-reacting antigens in carbonate-washed ER and glyoxysomal membranes. The 62 kD subunit, found predominantly in glyoxysomes, was eluted form Con-A Sepharose by 0.5 M α-methylglucoside. An 86kD form present in 2-d ER (but not in 4-d ER) and glyoxysomes did not bind Con-A Sepharose. This form appears to be an unglycosylated precursor or the 62 kD subunit. A 67 kD form was the only species seen in 4-d ER. In a time course experiment, the 67 kD form appeared on the glyoxysomal membrane

  16. Biodiesel production by transesterification using immobilized lipase.

    Science.gov (United States)

    Narwal, Sunil Kumar; Gupta, Reena

    2013-04-01

    Biodiesel can be produced by transesterification of vegetable or waste oil catalysed by lipases. Biodiesel is an alternative energy source to conventional fuel. It combines environmental friendliness with biodegradability, low toxicity and renewability. Biodiesel transesterification reactions can be broadly classified into two categories: chemical and enzymatic. The production of biodiesel using the enzymatic route eliminates the reactions catalysed under acid or alkali conditions by yielding product of very high purity. The modification of lipases can improve their stability, activity and tolerance to alcohol. The cost of lipases and the relatively slower reaction rate remain the major obstacles for enzymatic production of biodiesel. However, this problem can be solved by immobilizing the enzyme on a suitable matrix or support, which increases the chances of re-usability. The main factors affecting biodiesel production are composition of fatty acids, catalyst, solvents, molar ratio of alcohol and oil, temperature, water content, type of alcohol and reactor configuration. Optimization of these parameters is necessary to reduce the cost of biodiesel production.

  17. Potencial de biocatálise enantiosseletiva de lipases microbianas Potential of enantioselective biocatalysis by microbial lipases

    OpenAIRE

    Patrícia de O. Carvalho; Silvana Ap. Calafatti; Maurício Marassi; Daniela M. da Silva; Fabiano J. Contesini; Renato Bizaco; Gabriela Alves Macedo

    2005-01-01

    Microbial lipases have a great potential for commercial applications due to their stability, selectivity and broad substrate specificity because many non-natural acids, alcohols or amines can be used as the substrate. Three microbial lipases isolated from Brazilian soil samples (Aspergillus niger; Geotrichum candidum; Penicillium solitum) were compared in terms of their stability and as biocatalysts in the enantioselective esterification using racemic substrates in organic medium. The lipase ...

  18. Novel Metagenome-Derived, Cold-Adapted Alkaline Phospholipase with Superior Lipase Activity as an Intermediate between Phospholipase and Lipase

    OpenAIRE

    Lee, Mi-Hwa; Oh, Ki-Hoon; Kang, Chul-Hyung; Kim, Ji-Hoon; Oh, Tae-Kwang; Ryu, Choong-Min; Yoon, Jung-Hoon

    2012-01-01

    A novel lipolytic enzyme was isolated from a metagenomic library obtained from tidal flat sediments on the Korean west coast. Its putative functional domain, designated MPlaG, showed the highest similarity to phospholipase A from Grimontia hollisae CIP 101886, though it was screened from an emulsified tricaprylin plate. Phylogenetic analysis showed that MPlaG is far from family I.6 lipases, including Staphylococcus hyicus lipase, a unique lipase which can hydrolyze phospholipids, and is more ...

  19. Up-regulation of mitochondrial activity and acquirement of brown adipose tissue-like property in the white adipose tissue of fsp27 deficient mice.

    Directory of Open Access Journals (Sweden)

    Shen Yon Toh

    Full Text Available Fsp27, a member of the Cide family proteins, was shown to localize to lipid droplet and promote lipid storage in adipocytes. We aimed to understand the biological role of Fsp27 in regulating adipose tissue differentiation, insulin sensitivity and energy balance. Fsp27(-/- mice and Fsp27/lep double deficient mice were generated and we examined the adiposity, whole body metabolism, BAT and WAT morphology, insulin sensitivity, mitochondrial activity, and gene expression changes in these mouse strains. Furthermore, we isolated mouse embryonic fibroblasts (MEFs from wildtype and Fsp27(-/- mice, followed by their differentiation into adipocytes in vitro. We found that Fsp27 is expressed in both brown adipose tissue (BAT and white adipose tissue (WAT and its levels were significantly elevated in the WAT and liver of leptin-deficient ob/ob mice. Fsp27(-/- mice had increased energy expenditure, lower levels of plasma triglycerides and free fatty acids. Furthermore, Fsp27(-/-and Fsp27/lep double-deficient mice are resistant to diet-induced obesity and display increased insulin sensitivity. Moreover, white adipocytes in Fsp27(-/- mice have reduced triglycerides accumulation and smaller lipid droplets, while levels of mitochondrial proteins, mitochondrial size and activity are dramatically increased. We further demonstrated that BAT-specific genes and key metabolic controlling factors such as FoxC2, PPAR and PGC1alpha were all markedly upregulated. In contrast, factors inhibiting BAT differentiation such as Rb, p107 and RIP140 were down-regulated in the WAT of Fsp27(-/- mice. Remarkably, Fsp27(-/- MEFs differentiated in vitro show many brown adipocyte characteristics in the presence of the thyroid hormone triiodothyronine (T3. Our data thus suggest that Fsp27 acts as a novel regulator in vivo to control WAT identity, mitochondrial activity and insulin sensitivity.

  20. Lipase immobilization and production of fatty acid methyl esters from canola oil using immobilized lipase

    International Nuclear Information System (INIS)

    Lipase enzyme from Aspergillus oryzae (EC 3.1.1.3) was immobilized onto a micro porous polymeric matrix which contains aldehyde functional groups and methyl esters of long chain fatty acids (biodiesel) were synthesized by transesterification of crude canola oil using immobilized lipase. Micro porous polymeric matrix was synthesized from styrene-divinylbenzene (STY-DVB) copolymers by using high internal phase emulsion technique and two different lipases, Lipozyme TL-100L® and Novozym 388®, were used for immobilization by both physical adsorption and covalent attachment. Biodiesel production was carried out with semi-continuous operation. Methanol was added into the reactor by three successive additions of 1:4 M equivalent of methanol to avoid enzyme inhibition. The transesterification reaction conditions were as follows: oil/alcohol molar ratio 1:4; temperature 40 oC and total reaction time 6 h. Lipozyme TL-100L® lipase provided the highest yield of fatty acid methyl esters as 92%. Operational stability was determined with immobilized lipase and it indicated that a small enzyme deactivation occurred after used repeatedly for 10 consecutive batches with each of 24 h. Since the process is yet effective and enzyme does not leak out from the polymer, the method can be proposed for industrial applications. -- Research highlights: → Lipozyme TL-100L and Novozym 388 were immobilized onto micro porous polymeric matrix by both physical adsorption and covalent linking. → Immobilized enzymes were used for synthesis of fatty acid methyl esters by transesterification of canola oil and methanol using semi-continuous operation system. → According to chromatographic analysis, Lipase Lipozyme TL-100L resulted in the highest yield of methyl ester as 92%.

  1. Immobilization of a Commercial Lipase from Penicillium camembertii (Lipase G by Different Strategies

    Directory of Open Access Journals (Sweden)

    Adriano A. Mendes

    2011-01-01

    Full Text Available The objective of this work was to select the most suitable procedure to immobilize lipase from Penicillium camembertii (Lipase G. Different techniques and supports were evaluated, including physical adsorption on hydrophobic supports octyl-agarose, poly(hydroxybutyrate and Amberlite resin XAD-4; ionic adsorption on the anionic exchange resin MANAE-agarose and covalent attachment on glyoxyl-agarose, MANAE-agarose cross-linked with glutaraldehyde, MANAE-agarose-glutaraldehyde, and epoxy-silica-polyvinyl alcohol composite. Among the tested protocols, the highest hydrolytic activity (128.2 ± 8.10 IU·g−1 of support was achieved when the lipase was immobilized on epoxy-SiO2-PVA using hexane as coupling medium. Lipase immobilized by ionic adsorption on MANAE-agarose also gave satisfactory result, attaining 55.6 ± 2.60 IU·g−1 of support. In this procedure, the maximum loading of immobilized enzyme was 9.3 mg·g−1 of gel, and the highest activity (68.8 ± 2.70 IU·g−1 of support was obtained when 20 mg of protein·g−1 was offered. Immobilization carried out in aqueous medium by physical adsorption on hydrophobic supports and covalent attachment on MANAE-agarose-glutaraldehyde and glyoxyl-agarose was shown to be unfeasible for Lipase G. Thermal stability tests revealed that the immobilized derivative on epoxy-SiO2-PVA composite using hexane as coupling medium had a slight higher thermal stability than the free lipase.

  2. Immobilization of a Commercial Lipase from Penicillium camembertii (Lipase G) by Different Strategies.

    Science.gov (United States)

    Mendes, Adriano A; Freitas, Larissa; de Carvalho, Ana Karine F; de Oliveira, Pedro C; de Castro, Heizir F

    2011-01-01

    The objective of this work was to select the most suitable procedure to immobilize lipase from Penicillium camembertii (Lipase G). Different techniques and supports were evaluated, including physical adsorption on hydrophobic supports octyl-agarose, poly(hydroxybutyrate) and Amberlite resin XAD-4; ionic adsorption on the anionic exchange resin MANAE-agarose and covalent attachment on glyoxyl-agarose, MANAE-agarose cross-linked with glutaraldehyde, MANAE-agarose-glutaraldehyde, and epoxy-silica-polyvinyl alcohol composite. Among the tested protocols, the highest hydrolytic activity (128.2 ± 8.10 IU·g(-1) of support) was achieved when the lipase was immobilized on epoxy-SiO(2)-PVA using hexane as coupling medium. Lipase immobilized by ionic adsorption on MANAE-agarose also gave satisfactory result, attaining 55.6 ± 2.60 IU·g(-1) of support. In this procedure, the maximum loading of immobilized enzyme was 9.3 mg·g(-1) of gel, and the highest activity (68.8 ± 2.70 IU·g(-1) of support) was obtained when 20 mg of protein·g(-1) was offered. Immobilization carried out in aqueous medium by physical adsorption on hydrophobic supports and covalent attachment on MANAE-agarose-glutaraldehyde and glyoxyl-agarose was shown to be unfeasible for Lipase G. Thermal stability tests revealed that the immobilized derivative on epoxy-SiO(2)-PVA composite using hexane as coupling medium had a slight higher thermal stability than the free lipase. PMID:21811674

  3. Homologous Expression of the Lipase and ABC Transporter Gene Cluster, tliDEFA, Enhances Lipase Secretion in Pseudomonas spp.

    OpenAIRE

    Ahn, Jung Hoon; Pan, Jae Gu; Rhee, Joon Shick

    2001-01-01

    The ABC transporter TliDEF was found to be an efficient secretory apparatus for extracellular lipase TliA in Pseudomonas fluorescens. For the enhanced secretion of the lipase, we tried to coexpress tliA and tliDEF in various Pseudomonas species. Whereas the coexpression of tliA and tliDEF was required for the lipase secretion in P. fragi, the expression of tliA was sufficient for the lipase secretion in P. fluorescens, P. syringae, and P. putida, indicating the existence of compatible ABC tra...

  4. FATTY-ACID COMPOSITION OF HUMAN-MILK TRIGLYCERIDE SPECIES - POSSIBLE CONSEQUENCES FOR OPTIMAL STRUCTURES OF INFANT FORMULA TRIGLYCERIDES

    NARCIS (Netherlands)

    WINTER, CH; HOVING, EB; MUSKIET, FAJ

    1993-01-01

    Human milk triglycerides (TGs) were separated into 14 fractions by silver ion high-performance liquid chromatography (HPLC) with light-scattering detection (LSD). Subsequent fractionation by reversed-phase HPLC-LSD resulted in 75 subfractions. The major 48 were analysed by gas chromatography for the

  5. Lipase - Catalyzed glycerolysis of sunflower oil to produce partial glycerides.

    Directory of Open Access Journals (Sweden)

    Zaher, F. A.

    1998-12-01

    Full Text Available Partial glycerides were prepared by glycerolysis of sunflower oil in presence of lipase enzyme as catalyst. Six lipases of different origins were used and compared for their catalytic activity. These include Chromobacterium lipase, pancreatic lipase, Rhizopus arrhizus lipase, lyophilized lipase (plant lipase in addition to two lipase preparations derived from Rhizopus japonicas; Lilipase A-10 and Lilipase B-2. Chromobacterium lipase was found to be the most active as glycerolysis catalyst whereas lyophilized lipase; a plant preparation from wheat germ was the least active. The results have also shown that the lipase type affects also the product polarity and hence its field of application as a food emulsifier. Less polar products can be obtained using Chromobacterium lipase whereas the more polar ones using a fungal lipase preparation «Lipase A-10». The product polarity is also influenced by the process temperature but the mode of its effect is different for different lipases.

    Se prepararon glicéridos parciales mediante glicerolisis de aceite de girasol en presencia de lipasa como catalizador. Seis lipasas de orígenes diferentes se utilizaron y compararon en función de su actividad catalítica. Estas incluyeron lipasa de Chromobacterium, lipasa pancreática, lipasa de Rhizopus arrhizus, lipasa liofilizada (lipasa vegetal además de dos preparaciones de lipasa derivadas de Rhizopus japonicus: lilipase A-10 y lilipase B-2. Se encontró que la lipasa de Chromobacterium fue la más activa como catalizador en la glicerolisis mientras que la lipasa liofilizada, preparación vegetal a partir de germen de trigo, fue la menos activa. Los resultados mostraron que los tipos de lipasa afectan también a la polaridad de los productos y por tanto a los rendimientos en su aplicación como emulsificantes alimentarios. Los productos menos polares pueden obtenerse usando lipasa de

  6. New lipase assay using Pomegranate oil coating in microtiter plates.

    Science.gov (United States)

    Ülker, Serdar; Placidi, Camille; Point, Vanessa; Gadenne, Benoît; Serveau-Avesque, Carole; Canaan, Stéphane; Carrière, Frédéric; Cavalier, Jean-François

    2016-01-01

    Lipases play various roles in fat digestion, lipoprotein metabolism, and in the mobilization of fat stored in lipid bodies in animals, plants and microorganisms. In association with these physiological functions, there is an important field of research for discovering lipase inhibitors and developing new treatments of diseases such as obesity, atherosclerosis, diabetes and tuberculosis. In this context, the development of convenient, specific and sensitive analytical methods for the detection and assay of lipases and/or lipase inhibitors is of major importance. It is shown here that purified triacylglycerols (TAGs) from Punica granatum (Pomegranate) seed oil coated on microtiter plates can be used for the continuous assay of lipase activity by recording the variations with time of the UV absorption spectra at 275 nm. UV absorption is due the release of punicic acid (9Z,11E,13Z-octadeca-9,11,13-trienoic acid), a conjugated triene contained in Pomegranate oil. This new microtiter plate assay allows to accurately measure the activity of a wider range of lipases compared to the similar assay previously developed with Tung oil containing α-eleostearic acid (9Z,11E,13E-octadeca-9,11,13-trienoic acid), including the LipY lipase from Mycobacterium tuberculosis. Although punicic acid is a diastereoisomer of α-eleostearic acid, the Δ(13)cis double bound found in punicic acid gives a different structure to the acyl chain that probably favours the interaction of Pomegranate TAGs with the lipase active site. The microplate lipase assay using Pomegranate TAGs shows high sensitivity, reproducibility and remarkable relevance for the high-speed screening of lipases and/or lipase inhibitors directly from raw culture media without any purification step. PMID:26343557

  7. Butyl acetate synthesis using immobilized lipase in calcium alginate beads

    International Nuclear Information System (INIS)

    The esterification reaction of acetic acid and n-butanol using immobilized lipase encapsulated in calcium alginate beads (Lipase - CAB) and in chitosan coated calcium alginate beads (Lipase-CCAB) in n-hexane under mild reaction conditions were studied. Effects of temperature and substrate concentration (acetic acid and n-butanol) using Lipase - CAB, Lipase - CCAB and free lipase on the esterification reaction and their thermal stability towards esterification reaction were investigated. Results of temperature studies showed that the butyl acetate conversion increased with increase of temperature and reached the highest yield of about 70% around 50 degree Celsius for both immobilized systems but the yield of product catalyzed by free enzyme decreased as temperature was increased. Thermal stabilities studies showed that the Lipase-CCAB and Lipase-CAB were stable throughout the temperature range of 30-60 degree Celsius. However, free lipase became less stable at temperatures higher than 50 degree Celsius. The substrates, n-butanol and acetic acid exerted different effects on the esterification reaction and the reaction was favoured by higher acetic acid concentration than butanol. Kinetics parameters, Km and Vmax values for both substrates and the specific activities of the three enzyme system were also determined. The beads morphology was examined using SEM. Batch-wise operational stability studies for both immobilized systems demonstrated that the immobilized lipase performed better in the batch wise reactor system than the continuous bioreactor system and that the immobilized lipase remained active for at least 5 cycles of batch wise esterification reactions. (author)

  8. Regulation of lipoprotein lipase in primary cultures of isolated human adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Kern, P.A.; Marshall, S.; Eckel, R.H.

    1985-01-01

    To study the regulation of adipose tissue lipoprotein lipase (LPL) in human adipocytes, omental adipose tissue was obtained from healthy subjects and digested in collagenase. The isolated adipocytes thus obtained were suspended in Medium 199 and cultured at 37 degrees C. Cell viability was demonstrated in adipocytes cultured for up to 72 h by constancy of cell number, cell size, trypan-blue exclusion, and specific /sup 125/I-insulin binding. In addition, chloroquine induced an increase in cell-associated /sup 125/I-insulin at 24, 48, and 72 h after preparation. Thus, isolated adipocytes retained their ability to bind, internalize, and degrade insulin. LPL was measured as activity secreted into the culture medium (CM), released from cells by heparin (HR), and extracted from cell digests. A broad range of heparin concentrations produced a prompt release of LPL from a rapidly replenishable pool of cellular activity. When cells were cultured in medium containing 10% fetal bovine serum, there was a marked stimulation of CM and HR. The secretory response to serum (CM) correlated strongly with HR 24 h after preparation. In addition, HR was found to correlate logarithmically and inversely with body mass index. Insulin, at 400 ng/ml only, increased HR by 36 +/- 10%, an effect simulated by lower concentrations of insulin-like growth factor-1 (IGF1). Thus, LPL is produced and regulated in isolated human adipocytes. The degree of adiposity and serum are important regulators of HR activity, whereas insulin is stimulatory only at a pharmacologic concentration. This effect of insulin may be mediated through the IGF1 receptor. Isolated human adipocytes represent a novel and useful system for the study of LPL and lipid metabolism as well as for other aspects of adipocyte biology.

  9. Regulation of lipoprotein lipase in primary cultures of isolated human adipocytes

    International Nuclear Information System (INIS)

    To study the regulation of adipose tissue lipoprotein lipase (LPL) in human adipocytes, omental adipose tissue was obtained from healthy subjects and digested in collagenase. The isolated adipocytes thus obtained were suspended in Medium 199 and cultured at 37 degrees C. Cell viability was demonstrated in adipocytes cultured for up to 72 h by constancy of cell number, cell size, trypan-blue exclusion, and specific 125I-insulin binding. In addition, chloroquine induced an increase in cell-associated 125I-insulin at 24, 48, and 72 h after preparation. Thus, isolated adipocytes retained their ability to bind, internalize, and degrade insulin. LPL was measured as activity secreted into the culture medium (CM), released from cells by heparin (HR), and extracted from cell digests. A broad range of heparin concentrations produced a prompt release of LPL from a rapidly replenishable pool of cellular activity. When cells were cultured in medium containing 10% fetal bovine serum, there was a marked stimulation of CM and HR. The secretory response to serum (CM) correlated strongly with HR 24 h after preparation. In addition, HR was found to correlate logarithmically and inversely with body mass index. Insulin, at 400 ng/ml only, increased HR by 36 +/- 10%, an effect simulated by lower concentrations of insulin-like growth factor-1 (IGF1). Thus, LPL is produced and regulated in isolated human adipocytes. The degree of adiposity and serum are important regulators of HR activity, whereas insulin is stimulatory only at a pharmacologic concentration. This effect of insulin may be mediated through the IGF1 receptor. Isolated human adipocytes represent a novel and useful system for the study of LPL and lipid metabolism as well as for other aspects of adipocyte biology

  10. Ritonavir impairs lipoprotein lipase-mediated lipolysis and decreases uptake of fatty acids in adipose tissue

    NARCIS (Netherlands)

    den Boer, MAM; Berbee, JFP; Reiss, P; van der Valk, M; Voshol, PJ; Kuipers, F; Havekes, LM; Rensen, PCN; Romijn, JA

    2006-01-01

    Objective - The use of the HIV protease inhibitor ritonavir (RTV) is frequently associated with hypertriglyceridemia and lipodystrophy. The aim of our study was to determine the mechanism underlying the observed hypertriglyceridemia. Methods and Results - Feeding female APOE*3-Leiden transgenic mice

  11. Dietary Conjugated Linoleic Acid and Hepatic Steatosis: Species-Specific Effects on Liver and Adipose Lipid Metabolism and Gene Expression

    Directory of Open Access Journals (Sweden)

    Diwakar Vyas

    2012-01-01

    Full Text Available Objective. To summarize the recent studies on effect of conjugated linoleic acid (CLA on hepatic steatosis and hepatic and adipose lipid metabolism highlighting the potential regulatory mechanisms. Methods. Sixty-four published experiments were summarized in which trans-10, cis-12 CLA was fed either alone or in combination with other CLA isomers to mice, rats, hamsters, and humans were compared. Summary and Conclusions. Dietary trans-10, cis-12 CLA induces a severe hepatic steatosis in mice with a more muted response in other species. Regardless of species, when hepatic steatosis was present, a concurrent decrease in body adiposity was observed, suggesting that hepatic lipid accumulation is a result of uptake of mobilized fatty acids (FA from adipose tissue and the liver's inability to sufficiently increase FA oxidation and export of synthesized triglycerides. The potential role of liver FA composition, insulin secretion and sensitivity, adipokine, and inflammatory responses are discussed as potential mechanisms behind CLA-induced hepatic steatosis.

  12. Adipose tissues and thyroid hormones

    Directory of Open Access Journals (Sweden)

    Maria-Jesus eObregon

    2014-12-01

    Full Text Available The maintenance of energy balance is regulated by complex homeostatic mechanisms, including those emanating from adipose tissue. The main function of the adipose tissue is to store the excess of metabolic energy in the form of fat. The energy stored as fat can be mobilized during periods of energy deprivation (hunger, fasting, diseases. The adipose tissue has also a homeostatic role regulating energy balance and functioning as endocrine organ that secretes substances that control body homeostasis. Two adipose tissues have been identified: white and brown adipose tissues (WAT and BAT with different phenotype, function and regulation. WAT stores energy, while BAT dissipates energy as heat. Brown and white adipocytes have different ontogenetic origin and lineage and specific markers of WAT and BAT have been identified. Brite or beige adipose tissue has been identified in WAT with some properties of BAT. Thyroid hormones exert pleiotropic actions, regulating the differentiation process in many tissues including the adipose tissue. Adipogenesis gives raise to mature adipocytes and is regulated by several transcription factors (c/EBPs, PPARs that coordinately activate specific genes, resulting in the adipocyte phenotype. T3 regulates several genes involved in lipid mobilization and storage and in thermogenesis. Both WAT and BAT are targets of thyroid hormones, which regulate genes crucial for their proper function: lipogenesis, lipolysis, thermogenesis, mitochondrial function, transcription factors, the availability of nutrients. T3 acts directly through specific TREs in the gene promoters, regulating transcription factors. The deiodinases D3, D2 and D1 regulate the availability of T3. D3 is activated during proliferation, while D2 is linked to the adipocyte differentiation program, providing T3 needed for lipogenesis and thermogenesis. We examine the differences between BAT, WAT and brite/beige adipocytes and the process that activate UCP1 in WAT and

  13. Optimization of the Fermentation Conditions of Candida antarctica Lipase A in Pichia Pastoris using Response Surface Methodology%响应面法优化CALA在毕赤酵母中的组成型表达

    Institute of Scientific and Technical Information of China (English)

    严慧玲; 蓝东明; 王永华; 杨博

    2011-01-01

    In the present, Candida antarctica lipase A (CALA) is the only lipase that displaying a preference for position sn-2 of triglycerides opening a wide range of possible applications in synthesis of structured triglycerides. To enhance the lipase activity of CALA in Pichia Pastoris, the response surface methodology (RSM) was applied to optimize the fermentation conditions. After optimization, a second order model of the fermentation condition was established and was proved to be valid. Three significant factors affecting the lipase activity of CALA by fermentation in Pichia Pastoris were screened, which were the cultivation temperature, pH and the glucose concentration. The optimal conditions for CALA lipase activity were determined: pH 7.2, yeast extract concentration 10 g/L, glucose concentration 27 g/L, and cultivation temperature31 ℃.%南极假丝酵母脂肪酶A (CALA)是现有研究中唯一一种对甘油三酯sn-2位显示出偏好的脂肪酶.本文在完成CALA在毕赤酵母中组成型表达的基础上,为了提高CALA的酶活,采用响应面法建立了CALA发酵培养基和培养条件的二阶数学模型,并验证了模型的有效性;筛选出了2个影响毕赤酵母发酵产CALA的主要因素:培养温度、葡萄糖含量和初始pH;确定了优化的发酵条件:发酵时间为72h,初始pH值7.2、酵母粉10g/L、葡萄糖27g/L、温度31℃.

  14. Properties of an immobilized lipase of Bacillus coagulans BTS-1.

    Science.gov (United States)

    Kanwari, S S; Srivastava, M; Chimni, S S; Ghazi, I A; Kaushal, R K; Joshi, G K

    2004-01-01

    Lipase (EC 3.1.1.3) is a tri-acylglycerol ester hydrolase, catalysing the hydrolysis of tri-, di-, and mono-acylglycerols to glycerol and fatty acids. To study the effect of adsorption of a lipase obtained from Bacillus coagulans BTS-1, its lipase was immobilized on native and activated (alkylated) matrices, i.e. silica and celite. The effect of pH, temperature, detergents, substrates, alcohols, organic solvent etc. on the stability of the immobilized enzyme was evaluated. The gluteraldahyde or formaldehyde (at 1% and 2% concentration, v/v) activated matrix was exposed to the Tris buffered lipase. The enzyme was adsorbed/entrapped more rapidly on to the activated silica than on the activated celite. The immobilized lipase showed optimal activity at 50 degrees C following one-hour incubation. The lipase was specifically more hydrolytic to the medium C-length ester (p-nitro phenyl caprylate than p-nitro phenyl laurate). The immobilization/entrapment enhanced the stability of the lipase at a relatively higher temperature (50 degrees C) and also promoted enzyme activity at an acidic pH (pH 5.5). Moreover, the immobilized lipase was quite resistant to the denaturing effect of SDS.

  15. Two types of brown adipose tissue in humans.

    Science.gov (United States)

    Lidell, Martin E; Betz, Matthias J; Enerbäck, Sven

    2014-01-01

    During the last years the existence of metabolically active brown adipose tissue in adult humans has been widely accepted by the research community. Its unique ability to dissipate chemical energy stored in triglycerides as heat makes it an attractive target for new drugs against obesity and its related diseases. Hence the tissue is now subject to intense research, the hypothesis being that an expansion and/or activation of the tissue is associated with a healthy metabolic phenotype. Animal studies provide evidence for the existence of at least two types of brown adipocytes. Apart from the classical brown adipocyte that is found primarily in the interscapular region where it constitutes a thermogenic organ, a second type of brown adipocyte, the so-called beige adipocyte, can appear within white adipose tissue depots. The fact that the two cell types develop from different precursors suggests that they might be recruited and stimulated by different cues and therefore represent two distinct targets for therapeutic intervention. The aim of this commentary is to discuss recent work addressing the question whether also humans possess two types of brown adipocytes and to highlight some issues when looking for molecular markers for such cells.

  16. Resistance to diet-induced adiposity in cannabinoid receptor-1 deficient mice is not due to impaired adipocyte function

    Directory of Open Access Journals (Sweden)

    Oosterveer Maaike H

    2011-12-01

    Full Text Available Abstract Background Overactivity and/or dysregulation of the endocannabinoid system (ECS contribute to development of obesity. In vitro studies indicate a regulatory role for the cannabinoid receptor 1 (CB1 in adipocyte function and CB1-receptor deficient (CB1-/- mice are resistant to high fat diet-induced obesity. Whether this phenotype of CB1-/- mice is related to altered fat metabolism in adipose tissue is unknown. Methods We evaluated adipose tissue differentiation/proliferation markers and quantified lipogenic and lipolytic activities in fat tissues of CB1-/- and CB1+/+ mice fed a high-fat (HF or a high-fat/fish oil (HF/FO diet as compared to animals receiving a low-fat chow diet. Comparison between HF diet and HF/FO diet allowed to investigate the influence of dietary fat quality on adipose tissue biology in relation to CB1 functioning. Results The adiposity-resistant phenotype of the CB1-/- mice was characterized by reduced fat mass and adipocyte size in HF and HF/FO-fed CB1-/- mice in parallel to a significant increase in energy expenditure as compared to CB1+/+ mice. The expression levels of adipocyte differentiation and proliferation markers were however maintained in these animals. Consistent with unaltered lipogenic gene expression, the fatty acid synthesis rates in adipose tissues from CB1-/- and CB1+/+ mice were unchanged. Whole-body and adipose-specific lipoprotein lipase (LPL activities were also not altered in CB1-/- mice. Conclusions These findings indicate that protection against diet-induced adiposity in CB1-deficient mice is not related to changes in adipocyte function per se, but rather results from increased energy dissipation by oxidative and non-oxidative pathways.

  17. Lipase-catalyzed synthesis of ascorbyl oleate in acetone: optimization of reaction conditions and lipase reusability.

    Science.gov (United States)

    Stojanović, Marija; Velićković, Dušan; Dimitrijević, Aleksandra; Milosavić, Nenad; Knežević-Jugović, Zorica; Bezbradica, Dejan

    2013-01-01

    Lipase-catalyzed ascorbyl oleate synthesis is eco-friendly and selective way of production of liposoluble biocompatible antioxidants, but still not present on an industrial level due to the high biocatalyst costs. In this study, response surface methodology was applied in order to estimate influence of individual experimental factors, identify interactions among them, and to determine optimum conditions for enzymatic synthesis of ascorbyl oleate in acetone, in terms of limiting substrate conversion, product yield, and yield per mass of consumed enzyme. As a biocatalyst, commercial immobilized preparation of lipase B from Candida antarctica, Novozym 435, was used. In order to develop cost-effective process, at reaction conditions at which maximum amount of product per mass of biocatalyst was produced (60°C, 0.018 % (v/v) of water, 0.135 M of vitamin C, substrates molar ratio 1:8, and 0.2 % (w/v) of lipase), possibilities for further increase of ester yield were investigated. Addition of molecular sieves at 4(th) hour of reaction enabled increase of yield from 16.7 mmol g⁻¹ to 19.3 mmol g⁻¹. Operational stability study revealed that after ten reaction cycles enzyme retained 48 % of its initial activity. Optimized synthesis with well-timed molecular sieves addition and repeated use of lipase provided production of 153 mmol per gram of enzyme. Further improvement of productivity was achieved using procedure for the enzyme reactivation. PMID:23985489

  18. Role of Triglyceride-rich Lipoproteins in Renal Injury

    OpenAIRE

    Ng, Kit Fai; AUNG, HNIN HNIN; Rutledge, John C.

    2011-01-01

    Dyslipidemia is implicated as a risk factor for the development of atherosclerosis. Specifically triglyceride-rich lipoproteins (TGRL) and their lipolysis products are shown to be pro-inflammatory and pro-apoptosis in both in vivo and in vitro studies with endothelium. However the role of TGRL in the progression of kidney diseases is not clear. Epidemiology studies demonstrated a correlation between renal disease and blood lipids. Recent evidence suggests that the mechanism may involve cellul...

  19. Secretory function of adipose tissue.

    Science.gov (United States)

    Kuryszko, J; Sławuta, P; Sapikowski, G

    2016-01-01

    There are two kinds of adipose tissue in mammals: white adipose tissue - WAT and brown adipose tissue - BAT. The main function of WAT is accumulation of triacylglycerols whereas the function of BAT is heat generation. At present, WAT is also considered to be an endocrine gland that produces bioactive adipokines, which take part in glucose and lipid metabolism. Considering its endocrine function, the adipose tissue is not a homogeneous gland but a group of a few glands which act differently. Studies on the secretory function of WAT began in 1994 after discovery of leptin known as the satiation hormone, which regulates body energy homeostasis and maintainence of body mass. Apart from leptin, the following belong to adipokines: adiponectin, resistin, apelin, visfatin and cytokines: TNF and IL 6. Adiponectin is a polypeptide hormone of antidiabetic, anti-inflammatory and anti-atherogenic activity. It plays a key role in carbohydrate and fat metabolism. Resistin exerts a counter effect compared to adiponectin and its physiological role is to maintain fasting glycaemia. Visfatin stimulates insulin secretion and increases insulin sensitivity and glucose uptake by muscle cells and adipocytes. Apelin probably increases the insulin sensitivity of tissues. TNF evokes insulin resistance by blocking insulin receptors and inhibits insulin secretion. Approximately 30% of circulating IL 6 comes from adipose tissue. It causes insulin resistance by decreasing the expression of insulin receptors, decreases adipogenesis and adiponectin and visfatin secretion, and stimulates hepatic gluconeogenesis. In 2004, Bays introduced the notion of adiposopathy, defined as dysfunction of the adipose tissue, whose main feature is insulin and leptin resistance as well as the production of inflammatory cytokines: TNF and IL 6 and monocyte chemoattractant protein. This means that excess of adipose tissue, especially visceral adipose tissue, leads to the development of a chronic subclinical

  20. Lipid droplet remodeling and interaction with mitochondria in mouse brown adipose tissue during cold treatment.

    Science.gov (United States)

    Yu, Jinhai; Zhang, Shuyan; Cui, Liujuan; Wang, Weiyi; Na, Huimin; Zhu, Xiaotong; Li, Linghai; Xu, Guoheng; Yang, Fuquan; Christian, Mark; Liu, Pingsheng

    2015-05-01

    Brown adipose tissue (BAT) maintains animal body temperature by non-shivering thermogenesis, which is through uncoupling protein 1 (UCP1) that uncouples oxidative phosphorylation and utilizes β-oxidation of fatty acids released from triacylglycerol (TAG) in lipid droplets (LDs). Increasing BAT activity and "browning" other tissues such as white adipose tissue (WAT) can enhance the expenditure of excess stored energy, and in turn reduce prevalence of metabolic diseases. Although many studies have characterized the biology of BAT and brown adipocytes, BAT LDs especially their activation induced by cold exposure remain to be explored. We have isolated LDs from mouse interscapular BAT and characterized the full proteome using mass spectrometry. Both morphological and biochemical experiments showed that the LDs could tightly associate with mitochondria. Under cold treatment mouse BAT started expressing LD structure protein PLIN-2/ADRP and increased expression of PLIN1. Both hormone sensitive lipase (HSL) and adipose TAG lipase (ATGL) were increased in LDs. In addition, isolated BAT LDs showed increased levels of the mitochondrial protein UCP1, and prolonged cold exposure could stimulate BAT mitochondrial cristae biogenesis. These changes were in agreement with the data from transcriptional analysis. Our results provide the BAT LD proteome for the first time and show that BAT LDs facilitate heat production by coupling increasing TAG hydrolysis through recruitment of ATGL and HSL to the organelle and expression of another LD resident protein PLIN2/ADRP, as well as by tightly associating with activated mitochondria. These findings will benefit the study of BAT activation and the interaction between LDs and mitochondria.

  1. Beneficial effects of adding lipase enzyme to broiler diet

    International Nuclear Information System (INIS)

    A total number of 300 Ross broiler chicks were obtained from commercial hatchery at one day of age. The chicks were divided into three groups (50 males and 50 females in each). The first and second groups were supplemented with 3000 and 2000 lU/kg diet of lipase enzyme, respectively, while the third group served as control and fed on basal diet. Birds fed on diets that supplemented with lipase enzyme showed significant increase in body weight and dry matter intake, as well as fats and protein content dry matters. The serum lipase activity showed significant increase in treated groups compared to the control. Non-significant changes were determined in serum total lipids, T3, T4 and ash content. Birds supplemented with lipase showed significant decrease in cholesterol concentration. It could be concluded that birds fed diets containing 2000 or 3000 lU/kg diet of lipase enzyme exhibited improvement in broiler performance

  2. Characteristic properties of lipase from cowpea (vigna unguiculata) seedlings

    International Nuclear Information System (INIS)

    Lipase activity was assayed in 4 days old cowpea seedlings using olive oil emulsion stabilized with 10% gum acacia as a substrate. The maximum lipase activity was observed at pH 8.0 with Tris-HCI buffer and at 30 degree C. The pH stability was found in between 7.5-8.5. Lipase activity was fairly stable up to 60 degree C and retaining 80% activity whereas, 26% lipase activity was remaining at 100 degree C within 15 minutes. Lipase activity was slightly increased in the presence of MnC/sub 2/ and decreased by the addition of Triton X 100, Tween 80, ZnCI/sub 2/ and mercaptoethanol. (author)

  3. Lowering triglycerides to modify cardiovascular risk: will icosapent deliver?

    Directory of Open Access Journals (Sweden)

    Scherer DJ

    2015-03-01

    Full Text Available Daniel J Scherer,1 Stephen J Nicholls2 1Cardiovascular Investigation Unit, Royal Adelaide Hospital, 2South Australian Health and Medical Research Institute, University of Adelaide, Adelaide, SA, Australia Abstract: Despite the clinical benefits of lowering levels of low-density lipoprotein cholesterol, many patients continue to experience cardiovascular events. This residual risk suggests that additional risk factors require aggressive modification to result in more effective prevention of cardiovascular disease. Hypertriglyceridemia has presented a considerable challenge with regard to understanding its role in the promotion of cardiovascular risk. Increasing evidence has established a clear causal role for elevated triglyceride levels in vascular risk. As a result, there is increasing interest in the development of specific therapeutic strategies that directly target hypertriglyceridemia. This has seen a resurgence in the use of omega-3 fatty acids for the therapeutic lowering of triglyceride levels. The role of these agents and other emerging strategies to reduce triglyceride levels in order to decrease vascular risk are reviewed. Keywords: hypertriglyceridemia, omega-3 fatty acid, fish oil, cardiovascular risk, lipids

  4. Skeletal muscle apolipoprotein B expression reduces muscular triglyceride accumulation

    DEFF Research Database (Denmark)

    Bartels, Emil D; Ploug, Thorkil; Størling, Joachim;

    2014-01-01

    Abstract Background. Lipid accumulation in skeletal muscle is associated with impaired insulin sensitivity in type 2 diabetes. In cardiac myocytes, lipoprotein secretion controlled by apolipoproteinB (apoB) and microsomal triglyceride transfer protein (MTP) affects lipid homeostasis. Design....... In this study, we investigated whether expression of a human apoB transgene affects triglyceride accumulation and insulin sensitivity in skeletal muscle in fat fed obese mice. Results. Expression of apoB and MTP mRNA and the human apoB transgene was seen in skeletal muscle of the transgene mice. Human apo......B transgenic mice accumulated 28% less triglycerides in skeletal myocytes after one year of fat-feeding as compared with WT mice (32 ± 5, n = 10 vs. 44 ± 4 nmol/mg ww, n = 13, p = 0.04). Moreover, expression of human apoB in fat-fed mice was associated with 32% (p = 0.02) and 37% (p = 0.01) lower plasma...

  5. Engineering of vascularized adipose constructs.

    Science.gov (United States)

    Wiggenhauser, Paul S; Müller, Daniel F; Melchels, Ferry P W; Egaña, José T; Storck, Katharina; Mayer, Helena; Leuthner, Peter; Skodacek, Daniel; Hopfner, Ursula; Machens, Hans G; Staudenmaier, Rainer; Schantz, Jan T

    2012-03-01

    Adipose tissue engineering offers a promising alternative to the current surgical techniques for the treatment of soft tissue defects. It is a challenge to find the appropriate scaffold that not only represents a suitable environment for cells but also allows fabrication of customized tissue constructs, particularly in breast surgery. We investigated two different scaffolds for their potential use in adipose tissue regeneration. Sponge-like polyurethane scaffolds were prepared by mold casting with methylal as foaming agent, whereas polycaprolactone scaffolds with highly regular stacked-fiber architecture were fabricated with fused deposition modeling. Both scaffold types were seeded with human adipose tissue-derived precursor cells, cultured and implanted in nude mice using a femoral arteriovenous flow-through vessel loop for angiogenesis. In vitro, cells attached to both scaffolds and differentiated into adipocytes. In vivo, angiogenesis and adipose tissue formation were observed throughout both constructs after 2 and 4 weeks, with angiogenesis being comparable in seeded and unseeded constructs. Fibrous tissue formation and adipogenesis were more pronounced on polyurethane foam scaffolds than on polycaprolactone prototyped scaffolds. In conclusion, both scaffold designs can be effectively used for adipose tissue engineering. PMID:21850493

  6. Minireview: adiposity, inflammation, and atherogenesis.

    Science.gov (United States)

    Lyon, Christopher J; Law, Ronald E; Hsueh, Willa A

    2003-06-01

    Adipose tissue is a dynamic endocrine organ that secretes a number of factors that are increasingly recognized to contribute to systemic and vascular inflammation. Several of these factors, collectively referred to as adipokines, have now been shown regulate, directly or indirectly, a number of the processes that contribute to the development of atherosclerosis, including hypertension, endothelial dysfunction, insulin resistance, and vascular remodeling. Several adipokines are preferentially expressed in visceral adipose tissue, and the secretion of proinflammatory adipokines is elevated with increasing adiposity. Not surprisingly, approaches that reduce adipose tissue depots, including surgical fat removal, exercise, and reduced caloric intake, improve proinflammatory adipokine levels and reduce the severity of their resultant pathologies. Systemic adipokine levels can also be favorably altered by treatment with several of the existing drug classes used to treat insulin resistance, hypertension, and hypercholesterolemia. Greater understanding of adipokine regulation, however, should result in the design of improved treatment strategies to control disease states associated with increase adiposity, an important outcome in view of the growing worldwide epidemic of obesity. PMID:12746274

  7. Disulfide Bond in Pseudomonas aeruginosa Lipase Stabilizes the Structure but Is Not Required for Interaction with Its Foldase

    OpenAIRE

    Liebeton, Klaus; Zacharias, Annette; Jaeger, Karl-Erich

    2001-01-01

    Pseudomonas aeruginosa secretes a 29-kDa lipase which is dependent for folding on the presence of the lipase-specific foldase Lif. The lipase contains two cysteine residues which form an intramolecular disulfide bond. Variant lipases with either one or both cysteines replaced by serines showed severely reduced levels of extracellular lipase activity, indicating the importance of the disulfide bond for secretion of lipase through the outer membrane. Wild-type and variant lipase genes fused to ...

  8. Mechanism of acetaldehyde-induced deactivation of microbial lipases

    Directory of Open Access Journals (Sweden)

    Jaeger Karl E

    2011-02-01

    Full Text Available Abstract Background Microbial lipases represent the most important class of biocatalysts used for a wealth of applications in organic synthesis. An often applied reaction is the lipase-catalyzed transesterification of vinyl esters and alcohols resulting in the formation of acetaldehyde which is known to deactivate microbial lipases, presumably by structural changes caused by initial Schiff-base formation at solvent accessible lysine residues. Previous studies showed that several lipases were sensitive toward acetaldehyde deactivation whereas others were insensitive; however, a general explanation of the acetaldehyde-induced inactivation mechanism is missing. Results Based on five microbial lipases from Candida rugosa, Rhizopus oryzae, Pseudomonas fluorescens and Bacillus subtilis we demonstrate that the protonation state of lysine ε-amino groups is decisive for their sensitivity toward acetaldehyde. Analysis of the diverse modification products of Bacillus subtilis lipases in the presence of acetaldehyde revealed several stable products such as α,β-unsaturated polyenals, which result from base and/or amino acid catalyzed aldol condensation of acetaldehyde. Our studies indicate that these products induce the formation of stable Michael-adducts at solvent-accessible amino acids and thus lead to enzyme deactivation. Further, our results indicate Schiff-base formation with acetaldehyde to be involved in crosslinking of lipase molecules. Conclusions Differences in stability observed with various commercially available microbial lipases most probably result from different purification procedures carried out by the respective manufacturers. We observed that the pH of the buffer used prior to lyophilization of the enzyme sample is of utmost importance. The mechanism of acetaldehyde-induced deactivation of microbial lipases involves the generation of α,β-unsaturated polyenals from acetaldehyde which subsequently form stable Michael-adducts with the

  9. Effect of prepartal ad libitum feeding of grass silage on transcriptional adaptations of the liver and subcutaneous adipose tissue in dairy cows during the periparturient period.

    Science.gov (United States)

    Selim, S; Kokkonen, T; Taponen, J; Vanhatalo, A; Elo, K

    2015-08-01

    Prepartal energy overfeeding may predispose cows to a state of increased insulin resistance with greater lipolysis after parturition. The aim of the study was to evaluate the effects of prepartal overfeeding in terms of abundant grass silage ration on the liver and subcutaneous adipose tissue (SAT) gene expression around parturition. Sixteen multiparous Finnish Ayrshire dairy cows were fed ad libitum either grass silage [high energy, HE; 144 MJ/d of metabolizable energy (ME) intake, n=8] or a mixture of grass silage, wheat straw, and rapeseed meal [55:40:5 (CON), 109 MJ/d of ME, n=8] during the dry period (58.2±4.89 d, mean ± standard deviation). Tissue biopsies and blood samples were collected at -14 (±4.98), 1, and 7 d relative to the actual parturition date. The HE cows had greater total dry matter intake, ME intake, and ME balance during the dry period than the CON cows. Compared with CON, the increases in body weight and body condition score were greater in HE during the dry period. Milk yield during the first 2 wk of lactation was not different between the groups. Plasma glucose, nonesterified fatty acids, insulin, glucagon, and β-hydroxybutyrate did not differ between the groups during the transition period. Dietary treatment did not affect hepatic triglyceride content; however, a delayed increase in hepatic total lipid content was observed in the HE cows at d 1 postpartum. Hepatic cytosolic phosphoenolpyruvate carboxykinase 1 mRNA expression was lower in HE than in CON at d 1 and 7 postpartum. Adiponectin receptor 1 and 2 mRNA abundance tended to be lower in SAT of HE than CON. Lower lipoprotein lipase, leptin, and stearoyl-coenzyme A desaturase mRNA abundances were observed at d 7 postpartum in SAT of the HE cows compared with the CON cows. We concluded that prepartal ad libitum feeding of grass silage may decrease insulin sensitivity and lipogenesis in SAT during peripartal period and may attenuate the increase of hepatic gluconeogenic capacity from

  10. Isolation of lipase producing thermophilic bacteria: optimization of production and reaction conditions for lipase from Geobacillus sp.

    Science.gov (United States)

    Mehta, Akshita; Kumar, Rakesh; Gupta, Reena

    2012-12-01

    Lipases catalyze the hydrolysis and the synthesis of esters formed from glycerol and long chain fatty acids. Lipases occur widely in nature, but only microbial lipases are commercially significant. In the present study, thirty-two bacterial strains, isolated from soil sample of a hot spring were screened for lipase production. The strain TS-4, which gave maximum activity, was identified as Geobacillus sp. at MTCC, IMTECH, Chandigarh. The isolated lipase producing bacteria were grown on minimal salt medium containing olive oil. Maximal quantities of lipase were produced when 30 h old inoculum was used at 10% (v/v) in production medium and incubated in shaking conditions (150 rpm) for 72 h. The optimal temperature and pH for the bacterial growth and lipase production were found to be 60°C and 9.5, respectively. Maximal enzyme production resulted when mustard oil was used as carbon source and yeast extract as sole nitrogen source at a concentration of 1% (v/v) and 0.15% (w/v), respectively. The different optimized reaction parameters were temperature 65°C, pH 8.5, incubation time 10 min and substrate p-nitrophenyl palmitate. The Km and Vmax values of enzyme were found to be 14 mM and 17.86 μmol ml-1min-1, respectively, with p-nitrophenyl palmitate as substrate. All metal ions studied (1 mM) increased the lipase activity. PMID:23195552

  11. Role of Hepatic Lipase and Endothelial Lipase in High-Density Lipoprotein-Mediated Reverse Cholesterol Transport

    NARCIS (Netherlands)

    Annema, Wijtske; Tietge, Uwe J. F.

    2011-01-01

    Reverse cholesterol transport (RCT) constitutes a key part of the atheroprotective properties of high-density lipoproteins (HDL). Hepatic lipase (HL) and endothelial lipase (EL) are negative regulators of plasma HDL cholesterol levels. Although overexpression of EL decreases overall macrophage-to-fe

  12. Low birth weight male guinea pig offspring display increased visceral adiposity in early adulthood.

    Directory of Open Access Journals (Sweden)

    Ousseynou Sarr

    Full Text Available Uteroplacental insufficiency (UPI-induced intrauterine growth restriction (IUGR predisposes individuals to adult visceral obesity. We postulated that low birth weight (LBW offspring, from UPI-induced IUGR pregnancies, would display a visceral adipose lipogenic molecular signature involving altered gene expression, phosphorylation status of proteins of the lipid synthesis pathway and microRNA (miR expression profile, occurring in association with increased visceral adiposity. Normal birth weight (NBW and LBW (obtained by uterine artery ablation male guinea pig pups were fed a control diet from weaning to 145 days and sacrificed. Despite being lighter at birth, LBW pups displayed body weights similar to NBW offspring at 145 days. At this age, which represents young adulthood, the relative weights of LBW epididymal white adipose tissue (EWAT and lipid content were increased; which was consistent with adipocyte hypertrophy in the LBW offspring. Additionally, the mRNA expression of lipid synthesis-related genes including acetyl-CoA carboxylase 1 (ACC1, diglyceride acyltransferase 2 (DGAT2 and peroxisome proliferator-activated receptor gamma 1 (PPARγ1, was increased in LBW EWAT. Further, LBW EWAT displayed decreased phospho-ACC (Ser79 and phospho-PPARγ (Ser273 proteins. Moreover, the mRNA expression of hormone-sensitive lipase (HSL and fatty acid binding protein 4 (FABP4, both involved in promoting adipose lipid storage, was increased in LBW EWAT. Finally, miR-24 and miR-103-2, miRs related to adipocyte development, were both increased in LBW EWAT. These findings indicate that, following an adverse in utero environment, lipid synthesis-related genes and miR expression, along with phosphorylation status of key regulators of lipid synthesis, appear to be chronically altered and occur in association with increased visceral adiposity in young adult IUGR male offspring.

  13. Regulation of HSL serine phosphorylation in skeletal muscle and adipose tissue.

    Science.gov (United States)

    Watt, Matthew J; Holmes, Anna G; Pinnamaneni, Srijan K; Garnham, Andrew P; Steinberg, Gregory R; Kemp, Bruce E; Febbraio, Mark A

    2006-03-01

    Hormone-sensitive lipase (HSL) is important for the degradation of triacylglycerol in adipose and muscle tissue, but the tissue-specific regulation of this enzyme is not fully understood. We investigated the effects of adrenergic stimulation and AMPK activation in vitro and in circumstances where AMPK activity and catecholamines are physiologically elevated in humans in vivo (during physical exercise) on HSL activity and phosphorylation at Ser(563) and Ser(660), the PKA regulatory sites, and Ser(565), the AMPK regulatory site. In human experiments, skeletal muscle, subcutaneous adipose and venous blood samples were obtained before, at 15 and 90 min during, and 120 min after exercise. Skeletal muscle HSL activity was increased by approximately 80% at 15 min compared with rest and returned to resting rates at the cessation of and 120 min after exercise. Consistent with changes in plasma epinephrine, skeletal muscle HSL Ser(563) and Ser(660) phosphorylation were increased by 27% at 15 min (P HSL Ser(565) phosphorylation and AMPK signaling were increased at 90 min during, and after, exercise. Phosphorylation of adipose tissue HSL paralleled changes in skeletal muscle in vivo, except HSL Ser(660) was elevated 80% in adipose compared with 35% in skeletal muscle during exercise. Studies in L6 myotubes and 3T3-L1 adipocytes revealed important tissue differences in the regulation of HSL. AMPK inhibited epinephrine-induced HSL activity in L6 myotubes and was associated with reduced HSL Ser(660) but not Ser(563) phosphorylation. HSL activity was reduced in L6 myotubes expressing constitutively active AMPK, confirming the inhibitory effects of AMPK on HSL activity. Conversely, in 3T3-L1 adipocytes, AMPK activation after epinephrine stimulation did not prevent HSL activity or glycerol release, which coincided with maintenance of HSL Ser(660) phosphorylation. Taken together, these data indicate that HSL activity is maintained in the face of AMPK activation as a result of

  14. Enzymatic interesterification of palm stearin and coconut oil by a dual lipase system

    DEFF Research Database (Denmark)

    Ibrahim, Nuzul Amri Bin; Guo, Zheng; Xu, Xuebing

    2008-01-01

    Enzymatic interesterification of palm stearin with coconut oil was conducted by applying a dual lipase system in comparison with individual lipase-catalyzed reactions. The results indicated that a synergistic effect occurred for many lipase combinations, but largely depending on the lipase species...

  15. INTERESTERIFICATION OF MILK-FAT WITH OLEIC-ACID CATALYZED BY IMMOBILIZED RHIZOPUS-ORYZAE LIPASE

    NARCIS (Netherlands)

    OBA, T; WITHOLT, B

    1994-01-01

    Milk fat was interesterified with oleic acid by catalysis of an immobilized lipase in a microaqueous two-phase system. A commercial lipase from Rhizopus oryzae and a controlled pore glass carrier were selected for preparation of an immobilized lipase. The prepared immobilized lipase showed a Michael

  16. Resistance to high-fat diet-induced obesity and altered expression of adipose-specific genes in HSL-deficient mice.

    Science.gov (United States)

    Harada, Kenji; Shen, Wen-Jun; Patel, Shailja; Natu, Vanita; Wang, Jining; Osuga, Jun-ichi; Ishibashi, Shun; Kraemer, Fredric B

    2003-12-01

    To elucidate the role of hormone-sensitive lipase (HSL) in diet-induced obesity, HSL-deficient (HSL-/-) and wild-type mice were fed normal chow or high-fat diets. HSL-/- mice were resistant to diet-induced obesity showing higher core body temperatures. Weight and triacylglycerol contents were decreased in white adipose tissue (WAT) but increased in both brown adipose tissue (BAT) and liver of HSL-/- mice. Serum insulin levels in the fed state and tumor necrosis factor-alpha mRNA levels in adipose tissues were higher, whereas serum levels of adipocyte complement-related protein of 30 kDa (ACRP30)/adiponectin and leptin, as well as mRNA levels of ACRP30/adiponectin, leptin, resistin, and adipsin in WAT, were lower in HSL-/- mice than in controls. Expression of transcription factors associated with adipogenesis (peroxisome proliferator-activated receptor-gamma, CAAT/enhancer-binding protein-alpha) and lipogenesis (carbohydrate response element-binding protein, adipocyte determination- and differentiation-dependent factor-1/sterol regulatory element-binding protein-1c), as well as of adipose differentiation markers (adipocyte lipid-binding protein, perilipin, lipoprotein lipase), lipogenic enzymes (glycerol-3-phosphate acyltransferase, acyl-CoA:diacylglycerol acyltransferase-1 and -2, fatty acid synthase, ATP citrate lyase) and insulin signaling proteins (insulin receptor, insulin receptor substrate-1, GLUT4), was suppressed in WAT but not in BAT of HSL-/- mice. In contrast, expression of genes associated with cholesterol metabolism (sterol-regulatory element-binding protein-2, 3-hydroxy-3-methylglutaryl-CoA reductase, acyl-CoA:cholesterol acyltransferase-1) and thermogenesis (uncoupling protein-2) was upregulated in both WAT and BAT of HSL-/- mice. Our results suggest that impaired lipolysis in HSL deficiency affects lipid metabolism through alterations of adipose differentiation and adipose-derived hormone levels.

  17. Triglyceride-mediated pathways and coronary disease: collaborative analysis of 101 studies

    DEFF Research Database (Denmark)

    Sarwar, Nadeem; Sandhu, Manjinder S; Ricketts, Sally L;

    2010-01-01

    Whether triglyceride-mediated pathways are causally relevant to coronary heart disease is uncertain. We studied a genetic variant that regulates triglyceride concentration to help judge likelihood of causality....

  18. Adiposity, type 2 diabetes and Alzheimer's disease

    OpenAIRE

    Luchsinger, José A.; Gustafson, Deborah R

    2009-01-01

    This manuscript provides a comprehensive review of the epidemiologic evidence linking the continuum of adiposity and type 2 diabetes (T2D) with Alzheimer's disease (AD). The mechanisms relating adiposity and T2D to AD may include hyperinsulinemia, advanced products of glycosilation, cerebrovascular disease, and products of adipose tissue metabolism. Elevated adiposity in middle age is related to a higher risk of AD but the data on this association in old age is conflicting. Several studies ha...

  19. Adipocyte hypertrophy, inflammation and fibrosis characterize subcutaneous adipose tissue of healthy, non-obese subjects predisposed to type 2 diabetes.

    Directory of Open Access Journals (Sweden)

    A M Josefin Henninger

    Full Text Available BACKGROUND: The adipose tissue is important for development of insulin resistance and type 2 diabetes and adipose tissue dysfunction has been proposed as an underlying cause. In the present study we investigated presence of adipocyte hypertrophy, and gene expression pattern of adipose tissue dysfunction in the subcutaneous adipose tissue of healthy, non-obese subjects predisposed to type 2 diabetes compared to matched control subjects with no known genetic predisposition for type 2 diabetes. METHOD: Seventeen healthy and non-obese subjects with known genetic predisposition for type 2 diabetes (first-degree relatives, FDRs and 17 control subjects were recruited. The groups were matched for gender and BMI and had similar age. Glucose tolerance was determined by an oral glucose tolerance test and insulin sensitivity was calculated using HOMA-index. Blood samples were collected and subcutaneous abdominal adipose tissue biopsies obtained for gene expression analysis and adipocyte cell size measurement. RESULTS: Our findings show that, in spite of similar age, BMI and percent body fat, FDRs displayed adipocyte hypertrophy, as well as higher waist/hip ratio, fasting insulin levels, HOMA-IR and serum triglycerides. Adipocyte hypertrophy in the FDR group, but not among controls, was associated with measures of impaired insulin sensitivity. The adipocyte hypertrophy was accompanied by increased inflammation and Wnt-signal activation. In addition, signs of tissue remodeling and fibrosis were observed indicating presence of early alterations associated with adipose tissue dysfunction in the FDRs. CONCLUSION: Genetic predisposition for type 2 diabetes is associated with impaired insulin sensitivity, adipocyte hypertrophy and other markers of adipose tissue dysfunction. A dysregulated subcutaneous adipose tissue may be a major susceptibility factor for later development of type 2 diabetes.

  20. Raman Spectroscopic Analysis of Biochemical Changes in Individual Triglyceride-Rich Lipoproteins in the Pre- and Postprandial State

    Energy Technology Data Exchange (ETDEWEB)

    Chan, J; Motton, D; Rutledge, J; Keim, N; Huser, T

    2004-09-13

    Individual triglyceride-rich lipoprotein (TGRL) particles derived from human volunteers are non-destructively analyzed by laser tweezers Raman microspectroscopy and information on their composition and distribution is obtained. The Raman signature of single optically trapped very low-density lipoproteins (VLDL), a subclass of TGRL, which play an important role in cardiovascular disease, exhibits distinct peaks associated with molecular vibrations of fatty acids, proteins, lipids, and structural rearrangements of lipids. Our analysis of pre- and postprandial VLDL exhibits the signature of biochemical changes in individual lipoprotein particles following the consumption of meals. Interaction of VLDL with endothelium leads to the breakdown of complex triacylglycerols and the formation of a highly ordered core of free saturated fatty acids in the particle. A particle distribution analysis reveals trends in the degree to which this process has occurred in particles at different times during the postprandial period. Differences in particle distributions based on the different ratios of polyunsaturated to saturated fats in the consumed meals are also easily discerned. Individual lipoprotein particles hydrolyzed in-vitro through addition of lipoprotein lipase (LpL) exhibit strikingly similar changes in their Raman spectra. These results demonstrate the feasibility of monitoring the dynamics of lipid metabolism of individual TGRL particles as they interact with LpL in the endothelial cell wall using Raman spectroscopy.