Long-chain fatty acid triglyceride (TG) metabolism disorder impairs male fertility: a study using adipose triglyceride lipase deficient mice.

Science.gov (United States)

Masaki, Hidetake; Kim, Namhyo; Nakamura, Hitomi; Kumasawa, Keiichi; Kamata, Eriko; Hirano, Ken-Ichi; Kimura, Tadashi

2017-07-01

Does the deletion of adipose triglyceride lipase (Atgl) gene impair male fertility? The deletion of Atgl gene impaired male fertility but the effect was partially reversed by a low long-chain triglyceride (TG) diet. ATGL specifically hydrolyses long-chain fatty acid TG to diacylglycerol and a high level of expression of ATGL in testes has been reported. However, the role of ATGL in male fertility is unknown. To investigate the effect of deletion of Atgl gene on male fertility, cauda epididymides and testes were collected from wild-type, heterozygous and homozygous Atgl-deficient mice at 10 weeks of age and epididymal sperm analysis and histological analysis of the testes were performed. To investigate whether a medium-chain triglycerides (MCTs) replacement diet mitigated the impaired male fertility by deletion of Atgl gene, homozygous Atgl-deficient mice were fed a MCT replacement diet, or a standard diet including long-chain triglycerides (LCTs) in a control group, for 6 weeks from 5 weeks of age (n = 22). The systematic and local effects of the MCT replacement diet on spermatogenesis and sperm maturation in the epididymis were analyzed at 10 weeks of age. Hematoxylin and eosin staining in paraffin-embedded sections of testes and Oil Red O staining in frozen sections of testes were performed. The epididymal sperm concentrations were analyzed. Statistical analyses were performed using the Student's t-test or Mann-Whitney U test with Shapiro-Wilk Normality test. Although heterozygous mice were fertile and showed a similar number of epididymal total and motile sperm concentrations to wild-type mice, the deletion of Atgl gene in homozygous mice led to accumulation of TG deposits in testes and impaired spermatogenesis. The deletion of Atgl gene also impaired the sperm maturation process required for sperm to acquire the ability to move forward in the epididymis. The MCT replacement diet for 6 weeks increased the plasma level of non-esterified fatty acid (NEFA) (1

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.

Interaction between the triglyceride lipase ATGL and the arf1 activator GBF1

KAUST Repository

Ellong, Emy Njoh; Soni, Krishnakant G.; Bui, Quynh-Trang; Sougrat, Rachid; Golinelli-Cohen, Marie-Pierre; Jackson, Catherine L.

2011-01-01

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.

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)....

Properties of a membrane-bound triglyceride lipase of rapeseed (Brassica napus L.) cotyledons.

Science.gov (United States)

Rosnitschek, I; Theimer, R R

1980-04-01

The properties of the alkaline lipase activity (EC 3.1.1.3) that was recovered almost completely from a microsomal membrane fraction of 4-d-old rapeseed (Brassica napus L.) cotyledons were studied employing a titrimetric test procedure. The apparent KM was 6.5 mmol l(-1), with emulgated sunflower oil as the substrate. The products of triglyceride hydrolysis in vitro were glycerol, free fatty acids, and minor amounts of mono- and diglycerides. Maximum lipase activity depended on the preincubation of the lipolytic membrane fraction in 0.15 mol l(-1) NaCl and on the presence of at least 0.1 mol l(-1) NaCl in the test mixture. Desoxycholate and up to 0.1 mol l(-1) CaCl2 also activated the enzyme while EDTA and detergents such as trito x-100, digitonin, tween 85, and sodium dodecylsulfate were inhibitory. The rapeseed lipase displayed a conspicuous substrate selectivity among different plant triglycerides; the activity was inversely correlated with the oleic acid content of the oils. Water-soluble triacetin and the phospholipid lecithin were not hydrolyzed. Increasing amounts of free fatty acids reduced lipase activity; erucic acid, a major component of rapeseed oil, exhibited the strongest effect, suggesting a possible role in the regulation of lipase activity in vivo. The data demonstrate that the lipolytic membrane fraction houses a triglyceride lipase with properties similar to other plant and animal lipases. It can both qualitatively and quantitatively account for the fat degradation in rapeseed cotyledons. The evidence that provides further reason to acknowledge the membranous appendices of the spherosomes as the intracellular site of lipolysis is discussed.

Triglyceride selectivity of immobilized Thermomyces lanuginosa lipase in interesterification

DEFF Research Database (Denmark)

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

2005-01-01

from tri-C4:0 to tri-C20:0, except for tri-C6:0, and in a series of unsaturated FA from tri-C18:1 to tri-C18:3. The quantification was performed by HPLC, and different methods of selectivity evaluation were used. None of the methods used showed any significant differences between the performances......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...

Chronic intermittent hypoxia induces atherosclerosis via activation of adipose angiopoietin-like 4.

Science.gov (United States)

Drager, Luciano F; Yao, Qiaoling; Hernandez, Karen L; Shin, Mi-Kyung; Bevans-Fonti, Shannon; Gay, Jason; Sussan, Thomas E; Jun, Jonathan C; Myers, Allen C; Olivecrona, Gunilla; Schwartz, Alan R; Halberg, Nils; Scherer, Philipp E; Semenza, Gregg L; Powell, David R; Polotsky, Vsevolod Y

2013-07-15

Obstructive sleep apnea is a risk factor for dyslipidemia and atherosclerosis, which have been attributed to chronic intermittent hypoxia (CIH). Intermittent hypoxia inhibits a key enzyme of lipoprotein clearance, lipoprotein lipase, and up-regulates a lipoprotein lipase inhibitor, angiopoietin-like 4 (Angptl4), in adipose tissue. The effects and mechanisms of Angptl4 up-regulation in sleep apnea are unknown. To examine whether CIH induces dyslipidemia and atherosclerosis by increasing adipose Angptl4 via hypoxia-inducible factor-1 (HIF-1). ApoE(-/-) mice were exposed to intermittent hypoxia or air for 4 weeks while being treated with Angptl4-neutralizing antibody or vehicle. In vehicle-treated mice, hypoxia increased adipose Angptl4 levels, inhibited adipose lipoprotein lipase, increased fasting levels of plasma triglycerides and very low density lipoprotein cholesterol, and increased the size of atherosclerotic plaques. The effects of CIH were abolished by the antibody. Hypoxia-induced increases in plasma fasting triglycerides and adipose Angptl4 were not observed in mice with germline heterozygosity for a HIF-1α knockout allele. Transgenic overexpression of HIF-1α in adipose tissue led to dyslipidemia and increased levels of adipose Angptl4. In cultured adipocytes, constitutive expression of HIF-1α increased Angptl4 levels, which was abolished by siRNA. Finally, in obese patients undergoing bariatric surgery, the severity of nocturnal hypoxemia predicted Angptl4 levels in subcutaneous adipose tissue. HIF-1-mediated increase in adipose Angptl4 and the ensuing lipoprotein lipase inactivation may contribute to atherosclerosis in patients with sleep apnea.

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)

Sedlakova, A.; Ahlers, I.; Praslicka, M.

1979-01-01

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)

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......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...... of substrate for oxidative metabolism. However, failure to efficiently suppress lipolysis when FFA demands are low can have serious metabolic consequences and is believed to be a key mechanism in the development of type 2 diabetes in obesity. Since the discovery of ATGL in 2004, substantial progress has been...

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

International Nuclear Information System (INIS)

Tran, Dang-Thuan; Lin, Yi-Jan; Chen, Ching-Lung; Chang, Jo-Shu

2014-01-01

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

Structure of the human hepatic triglyceride lipase gene

International Nuclear Information System (INIS)

Cai, Shengjian; Wong, D.M.; Chen, Sanhwan; Chan, L.

1989-01-01

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

Fasting and post-prandial adipose tissue lipoprotein lipase and hormone-sensitive lipase in obesity and type 2 diabetes.

Science.gov (United States)

Costabile, G; Annuzzi, G; Di Marino, L; De Natale, C; Giacco, R; Bozzetto, L; Cipriano, P; Santangelo, C; Masella, R; Rivellese, A A

2011-05-01

Fasting and post-prandial abnormalities of adipose tissue (AT) lipoprotein lipase (LPL) and hormone- sensitive lipase (HSL) activities may have pathophysiological relevance in insulin-resistant conditions. The aim of this study was to evaluate activity and gene expression of AT LPL and HSL at fasting and 6 h after meal in two insulin-resistant groups - obese with Type 2 diabetes and obese without diabetes - and in non-diabetic normal-weight controls. Nine obese subjects with diabetes, 10 with obesity alone, and 9 controls underwent measurements of plasma levels of glucose, insulin, and triglycerides before and after a standard fat-rich meal. Fasting and post-prandial (6 h) LPL and HSL activities and gene expressions were determined in abdominal subcutaneous AT needle biopsies. The diabetic obese subjects had significantly lower fasting and post-prandial AT heparin-releasable LPL activity than only obese and control subjects (pobese subjects compared to controls in both fasting condition and 6 h after the meal (pfasting and 6 h after meal measurements in either LPL or HSL activities and gene expressions. Lipolytic activities in AT are differently altered in obesity and Type 2 diabetes being HSL alteration associated with both insulin-resistant conditions and LPL with diabetes per se. These abnormalities are similarly observed in the fasting condition and after a fat-rich meal.

Lipase-katalysierte Synthese strukturierter Triglyceride: Verfahrensoptimierung und Erzeugung selektiver Lipasemutanten durch gerichtete Evolution

OpenAIRE

Schmid, Ulrike

1999-01-01

In der vorliegenden Arbeit wurde zum einen die Lipase-Katalysierte Synthese strukturierter Triglyceride, zum anderen die Veränderung der Kettenlängenselektivität der slip1-Lipase aus C. rugosa durch gerichtete Evolution untersucht. Besonderes Interesse galt der Synthese von strukturierten Triglyceriden des ABA-Typs, die aufgrund ihrer symmetrischen Struktur zur Therapie von Fettabsorptionsproblemen wie z.B. Pankreasinsuffizienz eingesetzt werden können. Besonderes Interesse galt dabei der ...

The Effect of Alcohol on Postprandial and Fasting Triglycerides

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Albert Van de Wiel

2012-01-01

Full Text Available Alcohol has a significant additive effect on the postprandial triglyceride peak when it accompanies a meal containing fat, especially saturated fat. This results from a decrease in the breakdown of chylomicrons and VLDL remnants due to an acute inhibitory effect of alcohol on lipoprotein lipase activity. Furthermore, alcohol increases the synthesis of large VLDL particles in the liver, which is the main source of triglycerides in the hypertriglyceridemia associated with chronic excessive alcohol intake. In case of chronic consumption, lipoprotein lipase activity seems to adapt itself. The effect of alcohol on adipose tissues is less clear. Sometimes, a severe hypertriglyceridemia induced by alcohol (SHIBA can be observed, especially in patients with type 2 diabetes mellitus and/or obesity increasing the risk of pancreatitis.

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

International Nuclear Information System (INIS)

Lanza-Jacoby, S.; Tabares, A.

1990-01-01

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

Investigation and functional characterization of rare genetic variants in the adipose triglyceride lipase in a large healthy working population.

Directory of Open Access Journals (Sweden)

Stefan Coassin

2010-12-01

Full Text Available Recent studies demonstrated a strong influence of rare genetic variants on several lipid-related traits. However, their impact on free fatty acid (FFA plasma concentrations, as well as the role of rare variants in a general population, has not yet been thoroughly addressed. The adipose triglyceride lipase (ATGL is encoded by the PNPLA2 gene and catalyzes the rate-limiting step of lipolysis. It represents a prominent candidate gene affecting FFA concentrations. We therefore screened the full genomic region of ATGL for mutations in 1,473 randomly selected individuals from the SAPHIR (Salzburg Atherosclerosis Prevention program in subjects at High Individual Risk Study using a combined Ecotilling and sequencing approach and functionally investigated all detected protein variants by in-vitro studies. We observed 55 novel mostly rare genetic variants in this general population sample. Biochemical evaluation of all non-synonymous variants demonstrated the presence of several mutated but mostly still functional ATGL alleles with largely varying residual lipolytic activity. About one-quarter (3 out of 13 of the investigated variants presented a marked decrease or total loss of catalytic function. Genetic association studies using both continuous and dichotomous approaches showed a shift towards lower plasma FFA concentrations for rare variant carriers and an accumulation of variants in the lower 10%-quantile of the FFA distribution. However, the generally rather small effects suggest either only a secondary role of rare ATGL variants on the FFA levels in the SAPHIR population or a recessive action of ATGL variants. In contrast to these rather small effects, we describe here also the first patient with "neutral lipid storage disease with myopathy" (NLSDM with a point mutation in the catalytic dyad, but otherwise intact protein.

Triglyceride-lowering effect of respiratory uncoupling in white adipose tissue

Czech Academy of Sciences Publication Activity Database

Rossmeisl, Martin; Kovář, J.; Syrový, Ivo; Flachs, Pavel; Bobková, D.; Kolář, František; Poledne, R.; Kopecký, Jan

2005-01-01

Roč. 13, č. 5 (2005), s. 835-844 ISSN 1071-7323 R&D Projects: GA ČR(CZ) GP303/03/P127; GA ČR(CZ) GA303/02/1220 Institutional research plan: CEZ:AV0Z5011922 Keywords : adipose tissue * uncoupling protein * lipoprotein lipase Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 3.972, year: 2005

Insulin action in adipose tissue and muscle in hypothyroidism.

Science.gov (United States)

Dimitriadis, George; Mitrou, Panayota; Lambadiari, Vaia; Boutati, Eleni; Maratou, Eirini; Panagiotakos, Demosthenes B; Koukkou, Efi; Tzanela, Marinela; Thalassinos, Nikos; Raptis, Sotirios A

2006-12-01

Although insulin resistance in thyroid hormone excess is well documented, information on insulin action in hypothyroidism is limited. To investigate this, a meal was given to 11 hypothyroid (HO; aged 45 +/- 3 yr) and 10 euthyroid subjects (EU; aged 42 +/- 4 yr). Blood was withdrawn for 360 min from veins (V) draining the anterior abdominal sc adipose tissue and the forearm and from the radial artery (A). Blood flow (BF) in adipose tissue was measured with 133Xe and in forearm with strain-gauge plethysmography. Tissue glucose uptake was calculated as (A-V)glucose(BF), lipoprotein lipase as (A-V)Triglycerides(BF), and lipolysis as [(V-A)glycerol(BF)]-lipoprotein lipase. The HO group had higher glucose and insulin levels than the EU group (P hypothyroidism: 1) glucose uptake in muscle and adipose tissue is resistant to insulin; 2) suppression of lipolysis by insulin is not impaired; and 3) hypertriglyceridemia is due to decreased clearance by the adipose tissue.

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

altogether, indicating an enhanced basal activity of this lipase. No change was found in the expression of diacylglycerol acyl transferase 1 (DGAT1) after training. Inhibition of HSL with a monospecific, small molecule inhibitor (76-0079) and stimulation of ATGL with CGI-58 revealed that significant ATGL...

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

Fatty acid composition of adipose tissue changes with weight loss. Palmitoleic acid as a possible marker of endogenous lipogenesis or its functions as a lipokine are under debate. Objective was to assess the predictive role of adipose triglycerides fatty acids in weight maintenance in participants...... 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...

Impact of training state on fasting-induced regulation of adipose tissue metabolism in humans

DEFF Research Database (Denmark)

Bertholdt, Lærke; Gudiksen, Anders; Stankiewicz, Tomasz

2018-01-01

Recruitment of fatty acids from adipose tissue is essential during fasting. However, the molecular mechanisms behind fasting-induced metabolic regulation in human adipose tissue and the potential impact of training state in this are unknown. Therefore, the aim of the present study was to investig......Recruitment of fatty acids from adipose tissue is essential during fasting. However, the molecular mechanisms behind fasting-induced metabolic regulation in human adipose tissue and the potential impact of training state in this are unknown. Therefore, the aim of the present study...... was to investigate 1) fasting-induced regulation of lipolysis and glyceroneogenesis in human adipose tissue as well as 2) the impact of training state on basal oxidative capacity and fasting-induced metabolic regulation in human adipose tissue. Untrained (VO2max 55ml......RNA content were higher in trained subjects than untrained subjects. In addition, trained subjects had higher adipose tissue hormone sensitive lipase Ser660 phosphorylation and adipose triglyceride lipase protein content as well as higher plasma free fatty acids concentration than untrained subjects during...

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...

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

Maternal diabetes can cause fetal macrosomia and increased risk of obesity, diabetes, and cardiovascular disease in adulthood of the offspring. Although increased transplacental lipid transport could be involved, the impact of maternal type 1 diabetes on molecular mechanisms for lipid transport...... 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......RNA expression of lipoprotein lipase and lysosomal lipase were similar in women with diabetes and the control group. Immunohistochemistry showed EL protein in syncytiotrophoblasts facing the maternal blood and endothelial cells facing the fetal blood in placentas from both normal women and women with diabetes...

Metabolic consequences of adipose triglyceride lipase deficiency in humans: an in vivo study in patients with neutral lipid storage disease with myopathy.

Science.gov (United States)

Natali, Andrea; Gastaldelli, Amalia; Camastra, Stefania; Baldi, Simona; Quagliarini, Fabiana; Minicocci, Ilenia; Bruno, Claudio; Pennisi, Elena; Arca, Marcello

2013-09-01

The role of adipose triglyceride lipase (ATGL) in intermediate substrates metabolism has not been fully elucidated in humans. Our objective was to evaluate the consequences of ATGL deficiency on body fat distribution, insulin sensitivity, fatty acids metabolism, and energy substrate utilization. Body composition and organ fat content were measured by bioimpedance and (1)H nuclear magnetic resonance spectroscopy; heart glucose metabolism by [(18)F]deoxyglucose positron emission tomography and insulin sensitivity and β-cell function by oral glucose tolerance and 2-step euglycemic-hyperinsulinemic clamp. Lipolysis ([(2)H5]glycerol turnover) and indirect calorimetry were evaluated at fasting, after oral glucose load, during the clamp, and also during an iv epinephrine infusion. These metabolic investigations were carried out during hospitalization. Three patients affected by neutral lipid storage disease with myopathy (NLSDM) due to homozygosity for loss-of-function mutations in the ATGL gene and 6 sex-, age-, and body mass index-matched controls were studied. As expected, NLSDM patients showed diffuse, although heterogeneous, fat infiltration in skeletal muscles associated with increased visceral fat. Although heart and liver were variably affected, fat content in the pancreas was increased in all patients. Compared with healthy controls, NLSDM patients showed impaired insulin response to glucose possibly related to the severe pancreatic steatosis, preserved whole-body insulin sensitivity, and a shift toward glucose metabolism in the heart. Fasting nonesterified fatty acid concentrations as well as basal lipolytic rates and the antilipolytic effect of insulin were normal in NLSDM patients, whereas the lipolytic effect of norepinephrine was impaired. Finally, no significant abnormality in the respiratory quotient was noted in NLSDM patients. In humans, ATGL has a remarkable effect on cellular lipid droplet handling, and its lack causes both perivisceral, skeletal

Palmitic acid follows a different metabolic pathway than oleic acid in human skeletal muscle cells; lower lipolysis rate despite an increased level of adipose triglyceride lipase.

Science.gov (United States)

Bakke, Siril S; Moro, Cedric; Nikolić, Nataša; Hessvik, Nina P; Badin, Pierre-Marie; Lauvhaug, Line; Fredriksson, Katarina; Hesselink, Matthijs K C; Boekschoten, Mark V; Kersten, Sander; Gaster, Michael; Thoresen, G Hege; Rustan, Arild C

2012-10-01

Development of insulin resistance is positively associated with dietary saturated fatty acids and negatively associated with monounsaturated fatty acids. To clarify aspects of this difference we have compared the metabolism of oleic (OA, monounsaturated) and palmitic acids (PA, saturated) in human myotubes. Human myotubes were treated with 100μM OA or PA and the metabolism of [(14)C]-labeled fatty acid was studied. We observed that PA had a lower lipolysis rate than OA, despite a more than two-fold higher protein level of adipose triglyceride lipase after 24h incubation with PA. PA was less incorporated into triacylglycerol and more incorporated into phospholipids after 24h. Supporting this, incubation with compounds modifying lipolysis and reesterification pathways suggested a less influenced PA than OA metabolism. In addition, PA showed a lower accumulation than OA, though PA was oxidized to a relatively higher extent than OA. Gene set enrichment analysis revealed that 24h of PA treatment upregulated lipogenesis and fatty acid β-oxidation and downregulated oxidative phosphorylation compared to OA. The differences in lipid accumulation and lipolysis between OA and PA were eliminated in combination with eicosapentaenoic acid (polyunsaturated fatty acid). In conclusion, this study reveals that the two most abundant fatty acids in our diet are partitioned toward different metabolic pathways in muscle cells, and this may be relevant to understand the link between dietary fat and skeletal muscle insulin resistance. Copyright © 2012 Elsevier B.V. All rights reserved.

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.

Triglyceride dependent differentiation of obesity in adipose tissues by FTIR spectroscopy coupled with chemometrics.

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Kucuk Baloglu, Fatma; Baloglu, Onur; Heise, Sebastian; Brockmann, Gudrun; Severcan, Feride

2017-10-01

The excess deposition of triglycerides in adipose tissue is the main reason of obesity and causes excess release of fatty acids to the circulatory system resulting in obesity and insulin resistance. Body mass index and waist circumference are not precise measure of obesity and obesity related metabolic diseases. Therefore, in the current study, it was aimed to propose triglyceride bands located at 1770-1720 cm -1 spectral region as a more sensitive obesity related biomarker using the diagnostic potential of Fourier Transform Infrared (FTIR) spectroscopy in subcutaneous (SCAT) and visceral (VAT) adipose tissues. The adipose tissue samples were obtained from 10 weeks old male control (DBA/2J) (n = 6) and four different obese BFMI mice lines (n = 6 per group). FTIR spectroscopy coupled with hierarchical cluster analysis (HCA) and principal component analysis (PCA) was applied to the spectra of triglyceride bands as a diagnostic tool in the discrimination of the samples. Successful discrimination of the obese, obesity related insulin resistant and control groups were achieved with high sensitivity and specificity. The results revealed the power of FTIR spectroscopy coupled with chemometric approaches in internal diagnosis of abdominal obesity based on the spectral differences in the triglyceride region that can be used as a spectral marker. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

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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

Lipoprotein lipase activity and chylomicron clearance in rats fed a high fat diet

International Nuclear Information System (INIS)

Brown, C.M.; Layman, D.K.

1988-01-01

The relationships of tissue and plasma lipoprotein lipase (LPL) activities to tissue uptake and plasma clearance of 14 C-labeled chylomicron-triglyceride ( 14 C-CM-TG) were studied in female rats fed isoenergetic and isonitrogenous control (12% kJ from fat) or high fat diets (72% kJ from fat) for 8 wk. Animals fed the high-fat diet had higher levels of fasting plasma triglycerides and lower LPL activities in heart, renal adipose tissue and post-heparin plasma. Changes in LPL activities of skeletal muscles varied among muscles with higher values in the soleus and plantaris (32-61%) and no differences in the gastrocnemius. The lower LPL activity in renal adipose tissue was associated with lower uptake of fatty acids from 14 C-CM-TG by adipose. Fatty-acid uptake from labeled TG was not associated with tissue LPL activity in other tissues. Clearance of 14 C-CM-TG from plasma and the half-lives of 14 C-CM-TG were similar in both dietary groups. These data indicate that tissue and plasma LPL activities are not a direct index of uptake of fatty acids by tissues or clearance of chylomicron triglycerides

Triglyceride synthesis in epididymal adipose tissue: contribution of glucose and non-glucose carbon sources.

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Bederman, Ilya R; Foy, Steven; Chandramouli, Visvanathan; Alexander, James C; Previs, Stephen F

2009-03-06

The obesity epidemic has generated interest in determining the contribution of various pathways to triglyceride synthesis, including an elucidation of the origin of triglyceride fatty acids and triglyceride glycerol. We hypothesized that a dietary intervention would demonstrate the importance of using glucose versus non-glucose carbon sources to synthesize triglycerides in white adipose tissue. C57BL/6J mice were fed either a low fat, high carbohydrate (HC) diet or a high fat, carbohydrate-free (CF) diet and maintained on 2H2O (to determine total triglyceride dynamics) or infused with [6,6-(2)H]glucose (to quantify the contribution of glucose to triglyceride glycerol). The 2H2O labeling data demonstrate that although de novo lipogenesis contributed approximately 80% versus approximately 5% to the pool of triglyceride palmitate in HC- versus CF-fed mice, the epididymal adipose tissue synthesized approximately 1.5-fold more triglyceride in CF- versus HC-fed mice, i.e. 37+/-5 versus 25+/-3 micromolxday(-1). The [6,6-(2)H]glucose labeling data demonstrate that approximately 69 and approximately 28% of triglyceride glycerol is synthesized from glucose in HC- versus CF-fed mice, respectively. Although these data are consistent with the notion that non-glucose carbon sources (e.g. glyceroneogenesis) can make substantial contributions to the synthesis of triglyceride glycerol (i.e. the absolute synthesis of triglyceride glycerol from non-glucose substrates increased from approximately 8 to approximately 26 micromolxday(-1) in HC- versus CF-fed mice), these observations suggest (i) the importance of nutritional status in affecting flux rates and (ii) the operation of a glycerol-glucose cycle.

The ANGPTL3-4-8 model, a molecular mechanism for triglyceride trafficking

OpenAIRE

Zhang, Ren

2016-01-01

Lipoprotein lipase (LPL) is a rate-limiting enzyme for hydrolysing circulating triglycerides (TG) into free fatty acids that are taken up by peripheral tissues. Postprandial LPL activity rises in white adipose tissue (WAT), but declines in the heart and skeletal muscle, thereby directing circulating TG to WAT for storage; the reverse is true during fasting. However, the mechanism for the tissue-specific regulation of LPL activity during the fed?fast cycle has been elusive. Recent identificati...

2017 George Lyman Duff Memorial Lecture: Fat in the Blood, Fat in the Artery, Fat in the Heart: Triglyceride in Physiology and Disease.

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Goldberg, Ira J

2018-04-01

Cholesterol is not the only lipid that causes heart disease. Triglyceride supplies the heart and skeletal muscles with highly efficient fuel and allows for the storage of excess calories in adipose tissue. Failure to transport, acquire, and use triglyceride leads to energy deficiency and even death. However, overabundance of triglyceride can damage and impair tissues. Circulating lipoprotein-associated triglycerides are lipolyzed by lipoprotein lipase (LpL) and hepatic triglyceride lipase. We inhibited these enzymes and showed that LpL inhibition reduces high-density lipoprotein cholesterol by >50%, and hepatic triglyceride lipase inhibition shifts low-density lipoprotein to larger, more buoyant particles. Genetic variations that reduce LpL activity correlate with increased cardiovascular risk. In contrast, macrophage LpL deficiency reduces macrophage function and atherosclerosis. Therefore, muscle and macrophage LpL have opposite effects on atherosclerosis. With models of atherosclerosis regression that we used to study diabetes mellitus, we are now examining whether triglyceride-rich lipoproteins or their hydrolysis by LpL affect the biology of established plaques. Following our focus on triglyceride metabolism led us to show that heart-specific LpL hydrolysis of triglyceride allows optimal supply of fatty acids to the heart. In contrast, cardiomyocyte LpL overexpression and excess lipid uptake cause lipotoxic heart failure. We are now studying whether interrupting pathways for lipid uptake might prevent or treat some forms of heart failure. © 2018 American Heart Association, Inc.

Lipidomic data on lipid droplet triglyceride remodelling associated with protection of breast cancer cells from lipotoxic stress

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Eva Jarc

2018-06-01

Full Text Available The data presented here is related to the research article entitled “Lipid droplets induced by secreted phospholipase A2 and unsaturated fatty acids protect breast cancer cells from nutrient and lipotoxic stress” by E. Jarc et al., Biochim. Biophys. Acta 1863 (2018 247–265. Elevated uptake of unsaturated fatty acids and lipid droplet accumulation are characteristic of aggressive cancer cells and have been associated with the cellular stress response. The present study provides lipidomic data on the triacylglycerol (TAG and phosphatidylcholine (PC composition of MDA-MB-231 breast cancer cells exposed to docosahexaenoic acid (DHA; 22:6, ω-3. Datasets provide information on the changes in lipid composition induced by depletion of adipose triglyceride lipase (ATGL and by exogenous addition of secreted phospholipase A2 (sPLA2 in DHA-treated cells. The presented alterations in lipid composition, mediated by targeting lipid droplet biogenesis and lipolysis, are associated with protection from lipotoxicity and allow further investigation into the role of lipid droplets in the resistance of cancer cells to lipotoxic stress. Keywords: Lipid droplets, Lipidomics, Adipose triglyceride lipase, Polyunsaturated fatty acid, Cancer, Phospholipase A2

Lipoprotein lipase activity in surgical patients: influence of trauma and infection.

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Robin, A P; Askanazi, J; Greenwood, M R; Carpentier, Y A; Gump, F E; Kinney, J M

1981-08-01

Hypertriglyceridemia commonly accompanies clinical sepsis and may be caused by increased hepatic production or decreased clearance of triglyceride from the bloodstream. In contrast, enhanced lipid clearing capacity is usually seen after uncomplicated trauma. The purpose of the study was to determine the role of lipoprotein lipase (LPL) in effecting the above changes. Enzyme activity was assayed in skeletal muscle and adipose tissue biopsy samples from 11 normal subjects and from 17 injured and 11 infected surgical patients. Normal subjects after 4 days of 5% dextrose infusion (D5) showed a significant decrease in adipose tissue LPL activity but no change in skeletal muscle activity. Trauma patients after several days of D5 had higher activity in adipose tissue and higher plasma insulin levels than diet-matched control subjects but showed no change in skeletal muscle activity. Infected patients with high plasma triglyceride levels had significantly decreased LPL activity in both tissues. A linear relationship was found between insulin concentration and adipose tissue LPL activity in normal subjects. We conclude that: (1) low tissue LPL activity in sepsis may result in diminished lipid clearance and contribute to hypertriglyceridemia, (2) after trauma, changes in tissue LPL activity as well as other factors such as altered hemodynamics play a role in determining in vivo lipid clearance, and (3) adipose tissue LPL activity is related to the plasma insulin concentration in normal subjects.

Loss of FTO in adipose tissue decreases Angptl4 translation and alters triglyceride metabolism.

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Wang, Chao-Yung; Shie, Shian-Sen; Wen, Ming-Shien; Hung, Kuo-Chun; Hsieh, I-Chang; Yeh, Ta-Sen; Wu, Delon

2015-12-15

A common variant of the FTO (fat mass- and obesity-associated) gene is a risk factor for obesity. We found that mice with an adipocyte-specific deletion of FTO gained more weight than control mice on a high-fat diet. Analysis of mice lacking FTO in adipocytes fed a normal diet or adipocytes from these mice revealed alterations in triglyceride metabolism that would be expected to favor increased fatty acid storage by adipose tissue. Mice lacking FTO in adipocytes showed increased serum triglyceride breakdown and clearance, which was associated with lower serum triglyceride concentrations. In addition, lipolysis in response to β-adrenergic stimulation was decreased in adipocytes and ex vivo adipose explants from the mutant mice. FTO is a nucleic acid demethylase that removes N(6)-methyladenosine (m(6)A) from mRNAs. We found that FTO bound to Angptl4, which encodes an adipokine that stimulates intracellular lipolysis in adipocytes. Unexpectedly, the adipose tissue of fasted or fed mice lacking FTO in adipocytes had greater Angptl4 mRNA abundance. However, after high-fat feeding, the mutant mice had less Angptl4 protein and more m(6)A-modified Angptl4 than control mice, suggesting that lack of FTO prevented the translation of Angptl4. Injection of Angptl4-encoding adenovirus into mice lacking FTO in adipocytes restored serum triglyceride concentrations and lipolysis to values similar to those in control mice and abolished excessive weight gain from a high-fat diet. These results reveal that FTO regulates fatty acid mobilization in adipocytes and thus body weight in part through posttranscriptional regulation of Angptl4. Copyright © 2015, American Association for the Advancement of Science.

Role of lipase from community-associated methicillin-resistant Staphylococcus aureus strain USA300 in hydrolyzing triglycerides into growth-inhibitory free fatty acids.

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Cadieux, Brigitte; Vijayakumaran, Vithooshan; Bernards, Mark A; McGavin, Martin J; Heinrichs, David E

2014-12-01

Part of the human host innate immune response involves the secretion of bactericidal lipids on the skin and delivery of triglycerides into abscesses to control invading pathogens. Two Staphylococcus aureus lipases, named SAL1 and SAL2, were identified in the community-associated methicillin-resistant S. aureus strain USA300, which, presumably, are produced and function to degrade triglycerides to release free fatty acids. We show that the SAL2 lipase is one of the most abundant proteins secreted by USA300 and is proteolytically processed from the 72-kDa proSAL2 to the 44-kDa mature SAL2 by the metalloprotease aureolysin. We show that spent culture supernatants had lipase activity on both short- and long-chain fatty acid substrates and that deletion of gehB, encoding SAL2, resulted in the complete loss of these activities. With the use of gas chromatography-mass spectrometry, we show that SAL2 hydrolyzed trilinolein to linoleic acid, a fatty acid with known antistaphylococcal properties. When added to cultures of USA300, trilinolein and, to a lesser extent, triolein inhibited growth in a SAL2-dependent manner. This effect was shown to be due to the enzymatic activity of SAL2 on these triglycerides, since the catalytically inactive SAL2 Ser412Ala mutant was incapable of hydrolyzing the triglycerides or yielding delayed growth in their presence. Overall, these results reveal that SAL2 hydrolyzes triglycerides of both short- and long-chain fatty acids and that the released free fatty acids have the potential to cause significant delays in growth, depending on the chemical nature of the free fatty acid. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Replacement of soybean oil by fish oil increases cytosolic lipases activities in liver and adipose tissue from rats fed a high-carbohydrate diets.

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Rodrigues, Angélica Heringer; Moreira, Carolina Campos Lima; Neves, Maria José; Botion, Leida Maria; Chaves, Valéria Ernestânia

2018-06-01

Several studies have demonstrated that fish oil consumption improves metabolic syndrome and comorbidities, as insulin resistance, nonalcoholic fatty liver disease, dyslipidaemia and hypertension induced by high-fat diet ingestion. Previously, we demonstrated that administration of a fructose-rich diet to rats induces liver lipid accumulation, accompanied by a decrease in liver cytosolic lipases activities. In this study, the effect of replacement of soybean oil by fish oil in a high-fructose diet (FRUC, 60% fructose) for 8 weeks on lipid metabolism in liver and epididymal adipose tissue from rats was investigated. The interaction between fish oil and FRUC diet increased glucose tolerance and decreased serum levels of triacylglycerol (TAG), VLDL-TAG secretion and lipid droplet volume of hepatocytes. In addition, the fish oil supplementation increased the liver cytosolic lipases activities, independently of the type of carbohydrate ingested. Our results firmly establish the physiological regulation of liver cytosolic lipases to maintain lipid homeostasis in hepatocytes. In epididymal adipose tissue, the replacement of soybean oil by fish oil in FRUC diet did not change the tissue weight and lipoprotein lipase activity; however, there was increased basal and insulin-stimulated de novo lipogenesis and glucose uptake. Increased cytosolic lipases activities were observed, despite the decreased basal and isoproterenol-stimulated glycerol release to the incubation medium. These findings suggest that fish oil increases the glycerokinase activity and glycerol phosphorylation from endogenous TAG hydrolysis. Our findings are the first to show that the fish oil ingestion increases cytosolic lipases activities in liver and adipose tissue from rats treated with high-carbohydrate diets. Copyright © 2018. Published by Elsevier Inc.

Triglyceride Metabolism under Attack

NARCIS (Netherlands)

Kersten, Sander

2017-01-01

Hydrolysis of circulating triglycerides is carried out by the enzyme lipoprotein lipase, which is transported and anchored to the capillary wall by the protein GPIHBP1. Recent evidence indicates that certain individuals develop autoantibodies against GPIHBP1, impairing lipoprotein lipase function

Synthesis, radiosynthesis and in vitro evaluation of 18F-Bodipy-C16/triglyceride as a dual modal imaging agent for brown adipose tissue.

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Andreas Paulus

Full Text Available Brown adipose tissue research is in the focus in the field of endocrinology. We designed a dual-modal fluorescent/PET fatty acid based tracer on commercially available Bodipy-C16, which can be synthesized to its corresponding triglyceride and which combines the benefits of fluorescent and PET imaging.Bodipy-C16 was coupled to 1,3-diolein resulting in Bodipy-triglyceride. Bodipy-C16 and Bodipy-triglyceride compounds were radiolabeled with 18F using an 18F/19F exchange reaction to yield a dual-modal imaging molecule. Uptake of radiolabeled and non-labeled Bodipy-C16 and Bodipy-triglyceride was analyzed by fluorescence imaging and radioactive uptake in cultured adipocytes derived from human brown adipose tissue and white adipose tissue.Bodipy-C16 and Bodipy-triglyceride were successfully radiolabeled and Bodipy-C16 showed high shelf life and blood plasma stability (99% from 0-4 h. The uptake of Bodipy-C16 increased over time in cultured adipocytes, which was further enhanced after beta-adrenergic stimulation with norepinephrine. The uptake of Bodipy-C16 was inhibited by oleic acid and CD36 inhibitor sulfosuccinimidyl-oleate. The poor solubility of Bodipy-triglyceride did not allow stability or in vitro experiments.The new developed dual modal fatty acid based tracers Bodipy-C16 and Bodipy-triglyceride showed promising results to stimulate further in vivo evaluation and will help to understand brown adipose tissues role in whole body energy expenditure.

α-Eleostearic acid-containing triglycerides for a continuous assay to determine lipase sn-1 and sn-3 regio-preference.

Science.gov (United States)

El Alaoui, Meddy; Soulère, Laurent; Noiriel, Alexandre; Queneau, Yves; Abousalham, Abdelkarim

2017-08-01

Lipases are essentially described as sn-1 and sn-3 regio-selective. Actually few methods are available to measure this lipase regio-selectivity, moreover they require chiral chromatography analysis or specific derivations which are discontinuous and time consuming. In this study we describe a new, convenient, sensitive and continuous spectrophotometric method to screen lipases regio-selectivity using synthetic triglycerides (TG) containing α-eleostearic acid (9Z, 11E, 13E-octadecatrienoic acid) either at the sn-1 position [1-α-eleostearoyl-2,3-octadecyl-sn-glycerol (sn-EOO)] or at the sn-3 position [1,2-octadecyl-3-α-eleostearoyl-sn-glycerol (sn-OOE)] and coated onto the wells of microtiter plates. A non-hydrolysable ether bond, with a non UV-absorbing alkyl chain, was introduced at the other sn positions to prevent acyl chain migration during TG synthesis or lipolysis. The synthesis of TG containing α-eleostearic acid was performed from S-glycidol in six steps to obtain sn-EOO and in five steps to sn-OOE. The α-eleostearic acid conjugated triene constitutes an intrinsic chromophore and, consequently, confers the strong UV absorption properties of this free fatty acid as well as of the TG harboring it. The lipase activity on coated sn-EOO or sn-OOE was measured by the increase in the absorbance at 272nm due to the transition of α-eleostearic acid from the adsorbed to the soluble state. Human and porcine pancreatic lipases, guinea pig pancreatic lipase related protein 2, Thermomyces lanuginosus lipase, Candida antarctica lipase A and Candida antarctica lipase B were all used to validate the assay. This continuous high-throughput screening method could determine directly without any processes after lipolysis the regio-selectivity of various lipases. Copyright © 2017 Elsevier B.V. All rights reserved.

A lipasin/Angptl8 monoclonal antibody lowers mouse serum triglycerides involving increased postprandial activity of the cardiac lipoprotein lipase.

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Fu, Zhiyao; Abou-Samra, Abdul B; Zhang, Ren

2015-12-21

Lipasin/Angptl8 is a feeding-induced hepatokine that regulates triglyceride (TAG) metabolism; its therapeutical potential, mechanism of action, and relation to the lipoprotein lipase (LPL), however, remain elusive. We generated five monoclonal lipasin antibodies, among which one lowered the serum TAG level when injected into mice, and the epitope was determined to be EIQVEE. Lipasin-deficient mice exhibited elevated postprandial activity of LPL in the heart and skeletal muscle, but not in white adipose tissue (WAT), suggesting that lipasin suppresses the activity of LPL specifically in cardiac and skeletal muscles. Consistently, mice injected with the effective antibody or with lipasin deficiency had increased postprandial cardiac LPL activity and lower TAG levels only in the fed state. These results suggest that lipasin acts, at least in part, in an endocrine manner. We propose the following model: feeding induces lipasin, activating the lipasin-Angptl3 pathway, which inhibits LPL in cardiac and skeletal muscles to direct circulating TAG to WAT for storage; conversely, fasting induces Angptl4, which inhibits LPL in WAT to direct circulating TAG to cardiac and skeletal muscles for oxidation. This model suggests a general mechanism by which TAG trafficking is coordinated by lipasin, Angptl3 and Angptl4 at different nutritional statuses.

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...... 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...

Activity and stability of immobilized lipases in lipase-catalyzed modification of peanut oil

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Soumanou Mohamed M.

2004-11-01

Full Text Available Fatty acid release during lipolysis of peanut oil using microbial free and immobilized lipases in aqueous media was developed. Immobilized lipase from Rhizomucor miehei (RML gave the best result from its ability to clive different fatty acids from peanut oil in such media. In organic solvent, interesterification of peanut oil with tricaprylin using immobilized lipases from RML, Chromobacterium viscosum (CVL and Candida rugosa (CRL was performed. The best substrate molar ratio of tricaprylin to peanut oil found was in the range 0.7 to 0.8. Using substrate molar ratio 0.7, high amount of structured triglyceride ST (about 35% MLM, 44% LML triglyceride fractions was obtained with lipase from RML in n-hexane. The results found in solvent free system were in some cases quite similar to that obtained in organic solvent. In nine successive batch interesterification in solvent free medium using immobilized RML and CRL, no significant loss of amount of both produced triacylglycerol fractions until batch 7 was observed with RML.

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...... lipase genotypes on triglycerides, HDL, and IHD. DESIGN: The cross-sectional study involved 9004 adults. The prospective study consisted of 8817 adults developing 1001 IHD events over 23 yr. The case-control study involved 7818 non-IHD individuals vs. cohorts of 915 and 1062 IHD patients, respectively....... 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...

Structured medium and long chain triglycerides show short-term increases in fat oxidation, but no changes in adiposity in men.

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Roynette, Catherine E; Rudkowska, Iwona; Nakhasi, Dilip K; Jones, Peter J H

2008-05-01

Medium chain triglycerides (MCT) have been suggested as modulators of human energy expenditure (EE) and thus may influence total and regional body fat distribution. To investigate in overweight men the effects of structured medium and long chain triglycerides on EE, substrate oxidation and body adiposity, compared to extra virgin olive oil (OO). In a 6 week single-blind crossover study, 23 overweight men were randomly assigned to consume a standard high-fat diet of which 75% total fat was provided as either structured medium and long chain triglycerides referred to as structured oil (StO), or OO. EE and body composition were measured using indirect calorimetry and magnetic resonance imaging, respectively, at weeks 1 and 6 of each phase. Body weight decreased (pstructured medium and long chain triglyceride oil increases short-term fat oxidation but fails to modulate body weight or adiposity through a change in EE.

Identification of cardiometabolic risk: visceral adiposity index versus triglyceride/HDL cholesterol ratio.

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Salazar, Martin R; Carbajal, Horacio A; Espeche, Walter G; Aizpurúa, Marcelo; Maciel, Pablo M; Reaven, Gerald M

2014-02-01

The plasma concentration ratio of triglyceride (TG)/high-density lipoprotein cholesterol (HDL-C) can identify cardiometabolic risk and cardiovascular disease. The visceral adiposity index is a sex-specific index, in which measurements of body mass index and waist circumference are combined with TG and HDL-C concentrations. The current analysis was initiated to see if the visceral adiposity index would improve the ability of the TG/HDL-C to identify increased cardiometabolic risk and outcome. Cardiometabolic data were obtained in 2003 from 926 apparently healthy individuals, 796 of whom were evaluated in 2012 for evidence of incident cardiovascular disease. The relationship between TG/HDL-C and values for visceral adiposity index was evaluated by Pearson's correlation coefficient. The relative risks for first cardiovascular event between individuals above and below the TG/HDL-C sex-specific cut points, and in the top quartile of visceral adiposity index versus the remaining 3 quartiles, were estimated using Cox proportional hazard models. TG/HDL-C concentration and visceral adiposity index were highly correlated (r = 0.99) in both men and women. Although more men (133 vs121) and women (73 vs 59) were identified as being at "high risk" by an elevated TG/HDL-C ratio, the individual cardiometabolic risk factors were essentially identical with either index used. However, the hazard ratio of developing cardiovascular disease was significantly increased in individuals with an elevated TG/HDL-C, whereas it was not the case when the visceral adiposity index was used to define "high risk." The visceral adiposity index does not identify individuals with an adverse cardiometabolic profile any better than the TG/HDL-C. Copyright © 2014 Elsevier Inc. All rights reserved.

Association of postprandial serum triglyceride concentration and serum canine pancreatic lipase immunoreactivity in overweight and obese dogs.

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Verkest, K R; Fleeman, L M; Morton, J M; Groen, S J; Suchodolski, J S; Steiner, J M; Rand, J S

2012-01-01

Hypertriglyceridemia has been proposed to contribute to the risk of developing pancreatitis in dogs. To determine associations between postprandial serum triglyceride concentrations and canine pancreatic lipase immunoreactivity (cPLI) concentrations or pancreatic disease. Thirty-five client-owned overweight (n = 25) or obese (n = 10) dogs weighing >10 kg. Healthy dogs were prospectively recruited for a cross-sectional study. Serum triglyceride concentrations were measured before and hourly for 12 hours after a meal. Fasting cPLI and canine trypsin-like immunoreactivity (cTLI) concentrations were assayed. Cut-off values for hypertriglyceridemia were set a priori for fasting (≥ 88, ≥ 177, ≥ 354, ≥ 885 mg/dL) and peak postprandial (≥ 133, ≥ 442, ≥ 885 mg/dL) triglyceride concentrations. The association between hypertriglyceridemia and high cPLI concentrations was assessed by exact logistic regression. Follow-up was performed 4 years later to determine the incidence of pancreatic disease. Eight dogs had peak postprandial triglycerides >442 mg/dL and 3 dogs had fasting serum cPLI concentrations ≥ 400 μg/L. Odds of high cPLI concentrations were 16.7 times higher in dogs with peak postprandial triglyceride concentrations ≥ 442 mg/dL relative to other dogs (P obese dogs with peak serum postprandial triglyceride concentrations ≥ 442 mg/dL after a standard meal are more likely to have serum cPLI concentrations ≥ 400 μg/L, but did not develop clinically important pancreatic disease. Copyright © 2011 by the American College of Veterinary Internal Medicine.

A lipasin/Angptl8 monoclonal antibody lowers mouse serum triglycerides involving increased postprandial activity of the cardiac lipoprotein lipase

OpenAIRE

Fu, Zhiyao; Abou-Samra, Abdul B.; Zhang, Ren

2015-01-01

Lipasin/Angptl8 is a feeding-induced hepatokine that regulates triglyceride (TAG) metabolism; its therapeutical potential, mechanism of action, and relation to the lipoprotein lipase (LPL), however, remain elusive. We generated five monoclonal lipasin antibodies, among which one lowered the serum TAG level when injected into mice, and the epitope was determined to be EIQVEE. Lipasin-deficient mice exhibited elevated postprandial activity of LPL in the heart and skeletal muscle, but not in whi...

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

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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.

Gallic Acid Alleviates Hypertriglyceridemia and Fat Accumulation via Modulating Glycolysis and Lipolysis Pathways in Perirenal Adipose Tissues of Rats Fed a High-Fructose Diet

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Da-Wei Huang

2018-01-01

Full Text Available This study investigated the ameliorative effect of gallic acid (GA on hypertriglyceridemia and fat accumulation in perirenal adipose tissues of high-fructose diet (HFD-induced diabetic rats. The previous results showed that orally administered GA (30 mg/kg body weight for four weeks significantly reduced the levels of plasma glucose and triglyceride (TG in HFD rats. GA also markedly decreased the perirenal adipose tissues weight of HFD rats in present study (p < 0.05. Western blot assay indicated that GA restored expression of insulin signaling-related proteins, such as insulin receptor (IR, protein kinase C-zeta (PKC-ζ, and glucose transporter-4 (GLUT4 in the perirenal adipose tissues of HFD rats. Moreover, GA enhanced expression of glycolysis-related proteins, such as phosphofructokinase (PFK and pyruvate kinase (PK, and increased the expression of lipolysis-related proteins, such as adipose triglyceride lipase (ATGL, which is involved in lipolysis in the perirenal adipose tissues of HFD rats. This study revealed that GA may alleviate hypertriglyceridemia and fat accumulation through enhancing glycolysis and lipolysis pathways in perirenal adipose tissues of HFD rats. These findings also suggest the potential of GA in preventing the progression of diabetes mellitus (DM complications.

Lipolytic and thermogenic depletion of adipose tissue in cancer cachexia.

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Tsoli, Maria; Swarbrick, Michael M; Robertson, Graham R

2016-06-01

Although muscle wasting is the obvious manifestation of cancer cachexia that impacts on patient quality of life, the loss of lipid reserves and metabolic imbalance in adipose tissue also contribute to the devastating impact of cachexia. Depletion of fat depots in cancer patients is more pronounced than loss of muscle and often precedes, or even occurs in the absence of, reduced lean body mass. Rapid mobilisation of triglycerides stored within adipocytes to supply the body with fatty acids in periods of high-energy demand is normally mediated through a well-defined process of lipolysis involving the lipases ATGL, HSL and MGL. Studies into how these lipases contribute to fat loss in cancer cachexia have revealed the prominent role for ATGL in initiating lipolysis during adipose tissue atrophy, together with links between tumour-derived factors and the signalling pathways that control lipid flux within fat cells. The recent findings of increased thermogenesis in brown fat during cancer cachexia indicate that metabolically active adipose tissue contributes to the imbalance in energy homeostasis involved in catabolic wasting. Such energetically futile use of fatty acids liberated from adipose tissue to generate heat represents a maladaptive response in conjunction with anorexia experienced by cancer patients. As IL-6 release by tumours provokes lipolysis and activates the thermogenic programme in brown fat, this review explores the overlap in dysregulated metabolic processes due to inflammatory mediators in cancer cachexia and other disease states characterised by elevated cytokines such as obesity and diabetes. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Two novel missense mutations in bovine ATGL gene and their ...

African Journals Online (AJOL)

Adipose triglyceride lipase (ATGL) as a triglyceride-specific lipase, plays a key role in the triglyceride liposis mobilization of fat tissue. In this study, based on the pyrosequencing technology, two novel missense mutations were identified, which were 3289 G>C in exon 6 bringing E277Q and 3514 A>T in exon 7 bringing ...

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

Maternal diabetes can cause fetal macrosomia and increased risk of obesity, diabetes, and cardiovascular disease in adulthood of the offspring. Although increased transplacental lipid transport could be involved, the impact of maternal type 1 diabetes on molecular mechanisms for lipid transport...... 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....... These results suggest that maternal type 1 diabetes is associated with TG accumulation and increased EL and HSL gene expression in placenta and that optimal metabolic control reduces these effects....

Mice lacking prostaglandin E receptor subtype 4 manifest disrupted lipid metabolism attributable to impaired triglyceride clearance.

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Cai, Yin; Ying, Fan; Song, Erfei; Wang, Yu; Xu, Aimin; Vanhoutte, Paul M; Tang, Eva Hoi-Ching

2015-12-01

Upon high-fat feeding, prostaglandin E receptor subtype 4 (EP4)-knockout mice gain less body weight than their EP4(+/+) littermates. We investigated the cause of the lean phenotype. The mice showed a 68.8% reduction in weight gain with diminished fat mass that was not attributable to reduced food intake, fat malabsorption, or increased energy expenditure. Plasma triglycerides in the mice were elevated by 244.9%. The increase in plasma triglycerides was independent of changes in hepatic very low density lipoprotein (VLDL)-triglyceride production or intestinal chylomicron-triglyceride synthesis. However, VLDL-triglyceride clearance was drastically impaired in the EP4-knockout mice. The absence of EP4 in mice compromised the activation of lipoprotein lipase (LPL), the key enzyme responsible for trafficking of plasma triglycerides into peripheral tissues. Deficiency in EP4 reduced hepatic mRNA expression of the transcriptional factor cAMP response element binding protein H (by 36.8%) and LPL activators, including apolipoprotein (Apo)a5 (by 40.2%) and Apoc2 (by 61.3%). In summary, the lean phenotype of EP4-deficient mice resulted from reduction in adipose tissue and accretion of other peripheral organs caused by impaired triglyceride clearance. The findings identify a new metabolic dimension in the physiologic role played by endogenous EP4. © FASEB.

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

International Nuclear Information System (INIS)

Landis, B.A.; Rotolo, F.S.; Meyers, W.C.; Clark, A.B.; Quarfordt, S.H.

1987-01-01

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

Down-regulation of adipose tissue lipoprotein lipase during fasting requires that a gene, separate from the lipase gene, is switched on.

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Bergö, Martin; Wu, Gengshu; Ruge, Toralph; Olivecrona, Thomas

2002-04-05

During short term fasting, lipoprotein lipase (LPL) activity in rat adipose tissue is rapidly down-regulated. This down-regulation occurs on a posttranslational level; it is not accompanied by changes in LPL mRNA or protein levels. The LPL activity can be restored within 4 h by refeeding. Previously, we showed that during fasting there is a shift in the distribution of lipase protein toward an inactive form with low heparin affinity. To study the nature of the regulatory mechanism, we determined the in vivo turnover of LPL activity, protein mass, and mRNA in rat adipose tissue. When protein synthesis was inhibited with cycloheximide, LPL activity and protein mass decreased rapidly and in parallel with half-lives of around 2 h, and the effect of refeeding was blocked. This indicates that maintaining high levels of LPL activity requires continuous synthesis of new enzyme protein. When transcription was inhibited by actinomycin, LPL mRNA decreased with half-lives of 13.3 and 16.8 h in the fed and fasted states, respectively, demonstrating slow turnover of the LPL transcript. Surprisingly, when actinomycin was given to fed rats, LPL activity was not down-regulated during fasting, indicating that actinomycin interferes with the transcription of a gene that blocks the activation of newly synthesized LPL protein. When actinomycin was given to fasted rats, LPL activity increased 4-fold within 6 h, even in the absence of refeeding. The same effect was seen with alpha-amanitin, another inhibitor of transcription. The response to actinomycin was much less pronounced in aging rats, which are obese and insulin-resistant. These data suggest a default state where LPL protein is synthesized on a relatively stable mRNA and is processed into its active form. During fasting, a gene is switched on whose product prevents the enzyme from becoming active even though synthesis of LPL protein continues unabated.

Lipasin, a novel nutritionally-regulated liver-enriched factor that regulates serum triglyceride levels.

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Zhang, Ren

2012-08-10

The metabolic syndrome, a common disorder including glucose intolerance and dyslipidemia, poses a major public health issue. Patients with high blood lipids, such as triglycerides, are at high risk in developing atherosclerotic cardiovascular diseases. To identify genes involved in metabolism, we performed RNA-seq experiments on the liver and fat in mice treated with a high-fat diet or fasting, and identified Gm6484 (named Lipasin) as a novel nutritionally regulated gene. Human LIPASIN is liver specific, while the mouse one is enriched in the liver and fat, including both brown and white adipose tissues. Obesity increases liver Lipasin, whereas fasting reduces its expression in fat. ANGPTL3 (Angiopoietin-like 3) and ANGPTL4 are critical regulators of blood lipids. LIPASIN shares homology with ANGPTL3's N-terminal domain that is needed for lipid regulation, and with ANGPTL4's N-terminal segment that mediates lipoprotein lipase (LPL) binding. Lipasin overexpression by adenoviruses in mice increases serum triglyceride levels, and a recombinant Lipasin inhibits LPL activity. Therefore, a potential mechanism for Lipasin-mediated triglyceride elevation is through reduced triglyceride clearance by LPL inhibition. Lipasin is thus a novel nutritionally-regulated liver-enriched factor that plays a role in lipid metabolism. Copyright © 2012 Elsevier Inc. All rights reserved.

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

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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. Copyright © 2013 Elsevier Ltd. All rights reserved.

Regulation of triglyceride metabolism by angiopoietin-like proteins

NARCIS (Netherlands)

Mattijssen, F.B.J.; Kersten, A.H.

2012-01-01

asma triglyceride concentrations are determined by the balance between production of the triglyceride-rich lipoproteins VLDL and chylomicrons in liver and intestine, and their lipoprotein lipase-mediated clearance in peripheral tissues. In the last decade, the group of Angiopoietin-like proteins has

Increasing insulin resistance accentuates the effect of triglyceride-associated loci on serum triglycerides during 5 years

DEFF Research Database (Denmark)

Justesen, Johanne M; Andersson, Ehm Astrid; 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 was to investigate the association between a serum triglyceride weighted genetic risk score (wGRS) and changes in fasting serum...... triglyceride level over 5 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 nondiabetic 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...

Resistin in Dairy Cows: Plasma Concentrations during Early Lactation, Expression and Potential Role in Adipose Tissue

Science.gov (United States)

Reverchon, Maxime; Ramé, Christelle; Cognié, Juliette; Briant, Eric; Elis, Sébastien; Guillaume, Daniel; Dupont, Joëlle

2014-01-01

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. PMID:24675707

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.

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...... hydrolytic rate of gastric lipase and pancreatic lipase, on their own or pancreatic lipase after gastric lipase on TAG droplets of similar size emulsified in either soy lecithin (SL) or in bovine milk phospholipids (MPL), more similar to human milk globule membrane lipids than soy lecithin. Gastric lipase...... for formulas for term-born infants....

Oral lipase activities and fat-taste receptors for fat-taste sensing in chickens.

Science.gov (United States)

Kawabata, Yuko; Kawabata, Fuminori; Nishimura, Shotaro; Tabata, Shoji

2018-01-01

It has been reported that a functional fat-taste receptor, GPR120, is present in chicken oral tissues, and that chickens can detect fat taste in a behavioral test. However, although triglycerides need to be digested to free fatty acids to be recognized by fat-taste receptors such as GPR120, it remains unknown whether lipase activities exist in chicken oral tissues. To examine this question, we first cloned another fat-taste receptor candidate gene, CD36, from the chicken palate. Then, using RT-PCR, we determined that GPR120 and CD36 were broadly expressed in chicken oral and gastrointestinal tissues. Also by RT-PCR, we confirmed that several lipase genes were expressed in both oral and gastrointestinal tissues. Finally, we analyzed the lipase activities of oral tissues by using a fluorogenic triglyceride analog as a lipase substrate. We found there are functional lipases in oral tissues as well as in the stomach and pancreas. These results suggested that chickens have a basic fat-taste reception system that incorporates a triglycerides/oral-lipases/free fatty acids/GPR120 axis and CD36 axis. Copyright © 2017 Elsevier Inc. All rights reserved.

Rat lingual lipase: partial purification, hydrolytic properties, and comparison with pancreatic lipase.

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Roberts, I M; Montgomery, R K; Carey, M C

1984-10-01

We have partially purified lingual lipase from the serous glands of rat tongue. With a combination of Triton X-100 extraction or Triton X-114 phase-separation techniques, Bio-Bead SM-2 treatment, dialysis, and gel filtration on Sephadex G-200 or Sephacryl S-300, we obtained a sparingly soluble lipid-free protein demonstrating hydrolytic activity against triglycerides and negligible phospholipase or cholesteryl esterase activities. Compared with homogenate, specific activities of the enzyme were enriched 3- to 5-fold prior to gel filtration and 10-fold after gel filtration. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration under denaturing conditions (6 M guanidine X HCl or 0.1% sodium dodecyl sulfate) revealed one major glycoprotein band with Mr approximately 50,000. Gel filtration of the active enzyme in 0.1% Triton X-100 gave an Mr approximately 270,000-300,000, suggesting extensive self-aggregation. With both tributyrin and triolein, the pH optimum of the purified enzyme was 4.0 and activity extended from pH 2.0 to 8.0. In contrast to purified human pancreatic lipase, lingual lipase hydrolyzed triglyceride emulsions and mixed micelles stabilized with both short-chain (dihexanoyl) and long-chain (egg) lecithin and were inhibited only slightly (18-25%) by micellar concentrations of two common bile salts, taurodeoxycholate and taurocholate. Our results suggest that the hydrolysis of dietary fat by lingual lipase may extend from the pharynx through the esophagus and stomach and into the upper small intestine.

Evaluation of pancreatic lipase activity by simple urine analysis after oral administration of a new iodine-131-labeled triglyceride

International Nuclear Information System (INIS)

Kropp, J.; Knapp, F.F. Jr.; Weyenberg, A.; McPherson, D.W.; Ambrose, K.R.; Callahan, A.P.; Bergmann, K. von; Biersack, H.J.

1994-01-01

A new iodine-131-labeled triglyceride analogue called ''MIPAG'' [1,2-dipalmitoyl-3-[(15-p-iodophenyl) pentadecan-1-oyl]rac-glycerol] has been prepared in which 15-(p-iodophenyl)pentadecanoic acid (IPPA) is attached to position-3. MIPAG has been developed for the evaluation of pancreatic exocrine function by simple urine analysis and has been evaluated in rats and humans. After oral administration, IPPA is released from the triglyceride by the action of pancreatic lipases followed by intestinal absorption and the principal IPPA metabolite (p-iodobenzoic acid. IBA) is primarily excreted in the urine. Excretion in the urine and feces was evaluated in rats, as well as the biodistribution in various organs over 21 days. Twenty patients without pancreatic disease (normals) and four patients with pancreatic insufficiency were also investigated. Following oral administration of 30 μCi of MIPAG, urine was collected for two successive 24-h periods. Blood samples were drawn and thin-layer chromatographic (TLC) analysis was performed on the serum lipid extracts. Urine from normals contained 44.9%±7.7% and 61.8%±8.4% of the administered activity after 24 and 48 h, respectively. The patients with pancreatic insufficiency excreted 13.1%±5.6% and 18.9%±6.2%, respectively, which was significantly decreased (P<0.001) compared with normals. The TLC profiles showed an increasing proportion of IBA with time. Urine analysis after oral administration of MIPAG thus appears to be an attractive new technique for the evaluation of pancreatic lipase activity by a simple urine analysis. (orig.)

The G-250A polymorphism in the hepatic lipase gene promoter is associated with changes in hepatic lipase activity and LDL cholesterol: The KANWU Study

DEFF Research Database (Denmark)

Lindi, Virpi; Schwab, Ursula; Louheranta, Anne

2007-01-01

BACKGROUND AND AIMS: Hepatic lipase (HL) catalyzes the hydrolysis of triglycerides and phospholipids from lipoproteins, and promotes the hepatic uptake of lipoproteins. A common G-250A polymorphism in the promoter of the hepatic lipase gene (LIPC) has been described. The aim was to study...

13C mixed triglyceride breath test: a noninvasive method to assess lipase activity in children.

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van Dijk-van Aalst, K; Van Den Driessche, M; van Der Schoor, S; Schiffelers, S; van't Westeinde, T; Ghoos, Y; Veereman-Wauters, G

2001-05-01

Results from the 13C mixed triglyceride (MTG) breath test correlate with duodenal lipase activity in adults. This noninvasive test is a potential screening and diagnostic tool for children with fat malabsorption. The aim of this study was to adapt the methodology of the MTG breath test to study test meals and sampling methods and to define normal values for healthy children of all age groups; premature and full-term infants have similar pancreatic lipase deficiencies. After parental consent was obtained, 12 premature infants ( 2 kg), 12 full-term infants (1-6 months old), 20 children (3-10 years old), and 20 teenagers (11-17 years old) were tested. All children were thriving well, had no gastrointestinal or respiratory problems, and had not received any medication that contained natural 13C. For the premature and full-term infants, a formula was prepared that had a low and stable natural 13C content mixed with 100 mg 13C-labeled MTG (1,3-distearyl, 2-[13C-carboxyl] octanoyl glycerol) and 1 g polyethylene-glycol 3350. The best accepted test meal for children over 3 years old was a slice of white bread with 5 g butter and 15 g chocolate paste, mixed with 250 mg 13C-labeled MTG, and a glass of 100 mL whole-fat milk. Children over 3 years old were able to blow through a straw in a vacutainer for collecting the breath samples. In children under 3 years old, expired air was collected by aspirating breath via a nasal prong. Carbon dioxide production was calculated according to weight, age, and sex. For healthy pediatric control participants, the mean values for cumulative excretion of 13CO2 as a percentage of the administered dose after 6 hours were 23.9 +/- 5.2% in premature infants, 31.9 +/- 7.7% in full-term infants, 32.5 +/- 5.3% in children, and 28.0 +/- 5.4% in teenagers. The mean value for healthy adults is 35.6% with a lower reference limit of 22.8%. Age-specific test meals and breath-sampling techniques for the MTG breath test were defined. The mean values for

Fat digestion by lingual lipase: mechanism of lipolysis in the stomach and upper small intestine.

Science.gov (United States)

Liao, T H; Hamosh, P; Hamosh, M

1984-05-01

Ten to 30% of dietary fat is hydrolyzed in the stomach by lingual lipase, an enzyme secreted from lingual serous glands. We investigated the substrate specificity of this enzyme as well as the potential of lingual lipase to act in the upper small intestine i.e., in the presence of bile salts and lecithin. The data presented show that partially purified preparations of rat lingual lipase and the lipase in gastric aspirates of newborn infants have identical substrate specificity: medium-chain triglycerides were hydrolyzed at rates 5-8-fold higher than long-chain triglycerides; the rat and human enzymes do not hydrolyze the ester bond of lecithin or cholesteryl-ester. In contrast to pancreatic lipase, the hydrolysis of triglycerides by lingual lipase is not inhibited by lecithin. But, similar to pancreatic lipase the activity of lingual lipase is inhibited by bile salts, the extent of inhibition varying with its nature and concentration. This inactivation is not prevented by colipase but is partially averted by lipids and protein, suggesting that lingual lipase can remain active in the duodenum. The pH optimum of the enzyme (2.2-6.5 in the rat and 3.5-6.0 in human gastric aspirates) is compatible with continued activity in the upper small intestine, especially during the neonatal period, when the luminal pH is under 6.5. The marked variation in lipase activity levels in gastric aspirates of newborn infants is probably due to individual variations in enzyme amounts. The characteristics of the lipase are however identical in infants with low, intermediate or high activity levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Insulin Clearance Is Associated with Hepatic Lipase Activity and Lipid and Adiposity Traits in Mexican Americans.

Directory of Open Access Journals (Sweden)

Artak Labadzhyan

Full Text Available Reduction in insulin clearance plays an important role in the compensatory response to insulin resistance. Given the importance of this trait to the pathogenesis of diabetes, a deeper understanding of its regulation is warranted. Our goal was to identify metabolic and cardiovascular traits that are independently associated with metabolic clearance rate of insulin (MCRI. We conducted a cross-sectional analysis of metabolic and cardiovascular traits in 765 participants from the Mexican-American Coronary Artery Disease (MACAD project who had undergone blood sampling, oral glucose tolerance test, euglycemic-hyperinsulinemic clamp, dual-energy X-ray absorptiometry, and carotid ultrasound. We assessed correlations of MCRI with traits from seven domains, including anthropometry, biomarkers, cardiovascular, glucose homeostasis, lipase activity, lipid profile, and liver function tests. We found inverse independent correlations between MCRI and hepatic lipase (P = 0.0004, insulin secretion (P = 0.0002, alanine aminotransferase (P = 0.0045, total fat mass (P = 0.014, and diabetes (P = 0.03. MCRI and apolipoprotein A-I exhibited a positive independent correlation (P = 0.035. These results generate a hypothesis that lipid and adiposity associated traits related to liver function may play a role in insulin clearance.

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

NARCIS (Netherlands)

van Hoek, Mandy; Dallinga-Thie, Geesje M.; Steyerberg, Ewout W.; 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

Lipolysis Response to Endoplasmic Reticulum Stress in Adipose Cells*

Science.gov (United States)

Deng, Jingna; Liu, Shangxin; Zou, Liangqiang; Xu, Chong; Geng, Bin; Xu, Guoheng

2012-01-01

In obesity and diabetes, adipocytes show significant endoplasmic reticulum (ER) stress, which triggers a series of responses. This study aimed to investigate the lipolysis response to ER stress in rat adipocytes. Thapsigargin, tunicamycin, and brefeldin A, which induce ER stress through different pathways, efficiently activated a time-dependent lipolytic reaction. The lipolytic effect of ER stress occurred with elevated cAMP production and protein kinase A (PKA) activity. Inhibition of PKA reduced PKA phosphosubstrates and attenuated the lipolysis. Although both ERK1/2 and JNK are activated during ER stress, lipolysis is partially suppressed by inhibiting ERK1/2 but not JNK and p38 MAPK and PKC. Thus, ER stress induces lipolysis by activating cAMP/PKA and ERK1/2. In the downstream lipolytic cascade, phosphorylation of lipid droplet-associated protein perilipin was significantly promoted during ER stress but attenuated on PKA inhibition. Furthermore, ER stress stimuli did not alter the levels of hormone-sensitive lipase and adipose triglyceride lipase but caused Ser-563 and Ser-660 phosphorylation of hormone-sensitive lipase and moderately elevated its translocation from the cytosol to lipid droplets. Accompanying these changes, total activity of cellular lipases was promoted to confer the lipolysis. These findings suggest a novel pathway of the lipolysis response to ER stress in adipocytes. This lipolytic activation may be an adaptive response that regulates energy homeostasis but with sustained ER stress challenge could contribute to lipotoxicity, dyslipidemia, and insulin resistance because of persistently accelerated free fatty acid efflux from adipocytes to the bloodstream and other tissues. PMID:22223650

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

Prior to hibernation, the brown bear (Ursus arctos) exhibits unparalleled weight gain. Unlike humans, weight gain in bears is associated with lower levels of circulating free fatty acids (FFA) and increased insulin sensitivity. Understanding how free-ranging brown bears suppress lipolysis when...... 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...

The suprachiasmatic nucleus drives day-night variations in postprandial triglyceride uptake into skeletal muscle and brown adipose tissue.

Science.gov (United States)

Moran-Ramos, Sofía; Guerrero-Vargas, Natali N; Mendez-Hernandez, Rebeca; Basualdo, Maria Del Carmen; Escobar, Carolina; Buijs, Ruud M

2017-12-01

What is the central question of this study? What are the factors influencing day-night variations in postprandial triglycerides? What is the main finding and its importance? Rats show low postprandial plasma triglyceride concentrations early in the active period that are attributable to a higher uptake by skeletal muscle and brown adipose tissue. We show that these day-night variations in uptake are driven by the suprachiasmatic nucleus, probably via a Rev-erbα-mediated mechanism and independent of locomotor activity. These findings highlight that the suprachiasmatic nucleus has a major role in day-night variations in plasma triglycerides and that disturbances in our biological clock might be an important risk factor contributing to development of postprandial hyperlipidaemia. Energy metabolism follows a diurnal pattern, mainly driven by the suprachiasmatic nucleus (SCN), and disruption of circadian regulation has been linked to metabolic abnormalities. Indeed, epidemiological evidence shows that night work is a risk factor for cardiovascular disease, and postprandial hyperlipidaemia is an important contributor. Therefore, the aim of this work was to investigate the factors that drive day-night variations in postprandial triglycerides (TGs). Intact and SCN-lesioned male Wistar rats were subjected to an oral fat challenge during the beginning of the rest phase (day) or the beginning of the active phase (night). The plasma TG profile was evaluated and tissue TG uptake assayed. After the fat challenge, intact rats showed lower postprandial plasma TG concentrations early in the night when compared with the day. However, no differences were observed in the rate of intestinal TG secretion between day and night. Instead, there was a higher uptake of TG by skeletal muscle and brown adipose tissue early in the active phase (night) when compared with the rest phase (day), and these variations were abolished in rats bearing bilateral SCN lesions. Rev-erbα gene expression

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...... in activity of both neutral lipase and glycogen phosphorylase. The increase in lipase activity during contractions was not influenced by sympathectomy or propranolol. Training diminished the epinephrine induced lipase activation in muscle but enhanced the activation as well as the overall concentration...

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

International Nuclear Information System (INIS)

Kuriyama, M.; Yoshida, H.; Suzuki, M.; Fujiyama, J.; Igata, A.

1990-01-01

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

Growth hormone-mediated breakdown of body fat

DEFF Research Database (Denmark)

Johansen, T.; Malmlöf, K.; Richelsen, Bjørn

2003-01-01

regimen. Twelve-month-old rats fed first a high-fat diet or a low-fat diet for 14 weeks were injected with saline or growth hormone (4 mg/kg/d) for four days or three weeks in different combinations with either high- or low-fat diets. In adipose tissue, growth hormone generally inhibited lipoprotein...... lipase and also attenuated the inhibiting effect of insulin on hormone-sensitive lipase activity. Growth hormone treatment combined with restricted high-fat feeding reduced the activity of both lipases in adipose tissue and stimulated hormone-sensitive lipase in muscle. Generally, plasma levels of free...... fatty acids, glycerol and cholesterol were reduced by growth hormone, and in combination with restricted high-fat feeding, triglyceride levels improved too. We conclude that growth hormone inhibits lipid storage in adipose tissue by reducing both lipoprotein lipase activity and insulin's inhibitory...

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 -...

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.

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.

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...

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...

PLTP activity in premenopausal women. Relationship with lipoprotein lipase, HDL, LDL, body fat, and insulin resistance.

Science.gov (United States)

Murdoch, S J; Carr, M C; Hokanson, J E; Brunzell, J D; Albers, J J

2000-02-01

Plasma phospholipid transfer protein (PLTP) is thought to play a major role in the facilitated transfer of phospholipids between lipoproteins and in the modulation of high density lipoprotein (HDL) particle size and composition. However, little has been reported concerning the relationships of PLTP with plasma lipoprotein parameters, lipolytic enzymes, body fat distribution, insulin, and glucose in normolipidemic individuals, particularly females. In the present study, 50 normolipidemic healthy premenopausal females were investigated. The relationships between the plasma PLTP activity and selected variables were assessed. PLTP activity was significantly and positively correlated with low density lipoprotein (LDL) cholesterol (r(s) = 0.53), apoB (r(s) = 0.44), glucose (r(s) = 0.40), HDL cholesterol (r(s) = 0.38), HDL(3) cholesterol (r(s) = 0.37), lipoprotein lipase activity (r(s) = 0.36), insulin (r(s) = 0.33), subcutaneous abdominal fat (r(s) = 0.36), intra-abdominal fat (r(s) = 0.29), and body mass index (r(s) = 0.29). HDL(2) cholesterol, triglyceride, and hepatic lipase were not significantly related to PLTP activity. As HDL(2) can be decreased by hepatic lipase and hepatic lipase is increased in obesity with increasing intra-abdominal fat, the participants were divided into sub-groups of non-obese (n = 35) and obese (n = 15) individuals and the correlation of PLTP with HDL(2) cholesterol was re-examined. In the non-obese subjects, HDL(2) cholesterol was found to be significantly and positively related to PLTP activity (r(s) = 0.44). Adjustment of the HDL(2) values for the effect of hepatic lipase activity resulted in a significant positive correlation between PLTP and HDL(2) (r(s) = 0.41), indicating that the strength of the relationship between PLTP activity and HDL(2) can be reduced by the opposing effect of hepatic lipase on HDL(2) concentrations. We conclude that PLTP-facilitated lipid transfer activity is related to HDL and LDL metabolism, as well as

Cardiac metabolism and mechanics are altered by genetic loss of lipoprotein triglyceride lipolysis.

Science.gov (United States)

Noh, Hye-Lim; Yamashita, Haruyo; Goldberg, Ira J

2006-12-01

Most circulating fatty acids are contained in lipoprotein triglycerides. For the heart to acquire these lipids, they must be broken down into free fatty acids via the enzyme lipoprotein lipase (LpL). Although it has long been known that hearts primarily use esterified fatty acids as fuel, different sources of fatty acids were thought to be interchangeable. By creating mice with neonatal and acute LpL deletion we showed that lipoprotein-derived fatty acids could not be replaced by albumin-associated free fatty acids. Loss of cardiac LpL forces the heart to increase its uptake of glucose, reduce fatty acid oxidation, and eventually leads to cardiac dysfunction. In contrast, cardiomyocyte specific overexpression of an anchored form of LpL leads to excess lipid uptake, induction of fatty acid oxidation genes, and dilated cardiomyopathy. Increasing lipid secretion from the heart or redirecting lipids to adipose tissue can alleviate this lipotoxic situation.

Metformin lowers plasma triglycerides by promoting VLDL-triglyceride clearance by brown adipose tissue in mice.

Science.gov (United States)

Geerling, Janine J; Boon, Mariëtte R; van der Zon, Gerard C; van den Berg, Sjoerd A A; van den Hoek, Anita M; Lombès, Marc; Princen, Hans M G; Havekes, Louis M; Rensen, Patrick C N; Guigas, Bruno

2014-03-01

Metformin is the first-line drug for the treatment of type 2 diabetes. Besides its well-characterized antihyperglycemic properties, metformin also lowers plasma VLDL triglyceride (TG). In this study, we investigated the underlying mechanisms in APOE*3-Leiden.CETP mice, a well-established model for human-like lipoprotein metabolism. We found that metformin markedly lowered plasma total cholesterol and TG levels, an effect mostly due to a decrease in VLDL-TG, whereas HDL was slightly increased. Strikingly, metformin did not affect hepatic VLDL-TG production, VLDL particle composition, and hepatic lipid composition but selectively enhanced clearance of glycerol tri[(3)H]oleate-labeled VLDL-like emulsion particles into brown adipose tissue (BAT). BAT mass and lipid droplet content were reduced in metformin-treated mice, pointing to increased BAT activation. In addition, both AMP-activated protein kinase α1 (AMPKα1) expression and activity and HSL and mitochondrial content were increased in BAT. Furthermore, therapeutic concentrations of metformin increased AMPK and HSL activities and promoted lipolysis in T37i differentiated brown adipocytes. Collectively, our results identify BAT as an important player in the TG-lowering effect of metformin by enhancing VLDL-TG uptake, intracellular TG lipolysis, and subsequent mitochondrial fatty acid oxidation. Targeting BAT might therefore be considered as a future therapeutic strategy for the treatment of dyslipidemia.

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. Copyright © 2015 Elsevier Inc. All rights reserved.

Mice lacking ANGPTL8 (Betatrophin) manifest disrupted triglyceride metabolism without impaired glucose homeostasis.

Science.gov (United States)

Wang, Yan; Quagliarini, Fabiana; Gusarova, Viktoria; Gromada, Jesper; Valenzuela, David M; Cohen, Jonathan C; Hobbs, Helen H

2013-10-01

Angiopoietin-like protein (ANGPTL)8 (alternatively called TD26, RIFL, Lipasin, and Betatrophin) is a newly recognized ANGPTL family member that has been implicated in both triglyceride (TG) and glucose metabolism. Hepatic overexpression of ANGPTL8 causes hypertriglyceridemia and increased insulin secretion. Here we examined the effects of inactivating Angptl8 on TG and glucose metabolism in mice. Angptl8 knockout (Angptl8(-/-)) mice gained weight more slowly than wild-type littermates due to a selective reduction in adipose tissue accretion. Plasma levels of TGs of the Angptl8(-/-) mice were similar to wild-type animals in the fasted state but paradoxically decreased after refeeding. The lower TG levels were associated with both a reduction in very low density lipoprotein secretion and an increase in lipoprotein lipase (LPL) activity. Despite the increase in LPL activity, the uptake of very low density lipoprotein-TG is markedly reduced in adipose tissue but preserved in hearts of fed Angptl8(-/-) mice. Taken together, these data indicate that ANGPTL8 plays a key role in the metabolic transition between fasting and refeeding; it is required to direct fatty acids to adipose tissue for storage in the fed state. Finally, glucose and insulin tolerance testing revealed no alterations in glucose homeostasis in mice fed either a chow or high fat diet. Thus, although absence of ANGPTL8 profoundly disrupts TG metabolism, we found no evidence that it is required for maintenance of glucose homeostasis.

Endothelial lipase is a major determinant of HDL level

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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

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.

Lipopolysaccharide significantly influences the hepatic triglyceride metabolism in growing pigs.

Science.gov (United States)

Liu, Zhiqing; Liu, Weifeng; Huang, Yanping; Guo, Jun; Zhao, Ruqian; Yang, Xiaojing

2015-06-30

In the practical commercial pig farms, inflammation is a perennial problem, yet most of studies on inflammation are focused on immune response. Actually, inflammation can induce body metabolism disorder which will finally influence animals' growth. In this study, we investigated the effect of acute inflammation on the triglyceride (TG) metabolism in the liver of growing pigs and the possible underlying mechanisms. Twelve male growing pigs were randomly divided into two groups, a control group (received saline) and a LPS group (intramuscular injected with 15 μg/kg LPS). Six hours after LPS injection, the pigs were euthanized and sampled. Biochemical indexes, inflammation factors, lipid metabolism related parameters and mitochondrial function were evaluated. The relationship between glucocorticoid receptor (GR) and the key enzymes of de novo lipogenesis were also investigated by chromatin immunoprecipitation assay (ChIP). LPS induced a serious inflammation in the liver of growing pigs proved by liver morphologic changes, the up-regulated plasma cortisol, tumor necrosis factor-α (TNF-α) content and gene expression of inflammation related genes in liver. For de novo lipogenesis, LPS significantly decreased the gene expression of fatty acid synthase (FAS), Acetyl-CoA carboxylase-1 (ACC-1) and Stearoyl-CoA desaturase-1 (SCD-1), and the protein expression of ACC-1 and SCD-1. For lipolysis, only the gene expression of adipose triglyceride lipase (ATGL) was decreased. LPS did nothing to the gene expression of hormone-sensitive lipase (HSL) and the lipolytic enzymes activities. For β-oxidation, LPS significantly increased the protein expression of CPT-1α, but the gene expression of mitochondrial DNA-encoded genes and the activities of mitochondrial complex IV and V demonstrated no obviously changes. Furthermore, ChIP results showed that LPS significantly decreased the level of GR binding to ACC-1 promoter. LPS infection has a profound impact on hepatic TG metabolism

Molecular Species of the Enzymatically Synthesized Polyunsaturated Fatty Acid Rich Triglyceride

OpenAIRE

長田, 恭一; 高橋, 是太郎; 羽田野, 六男; 細川, 雅史

1991-01-01

Enzymatic glyceride synthesis and acid interchange using icosapentaenoic acid (EPA), docosahexaenoic acid (DHA), γ-linolenic acid (GLA), and EPA and DHA concentrated saponified fatty acid mixture obtained from sardine oil were carried out through the use of four kinds of microbial lipases. Lipase TOYO (Chromobacterium viscosum) was the most effective enzyme for glyceride synthesis as well as acid interchange of triglyceride (TG) rich in polyunsaturated fatty acids. There was a general tendenc...

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. Copyright © 2016 Elsevier B.V. All rights reserved.

Entwicklung eines kontinuierlichen Verfahrens zur enzymkatalysierten Synthese eines strukturierten Triglycerides

OpenAIRE

Stadler, Hans-Gerhard

2005-01-01

Ausgangspunkt für die in der vorliegenden Arbeit durchgeführten Entwicklung eines kontinuierlichen Verfahrens zur Synthese des strukturierten Triglycerides 1,3-Oleyl-2-palmitoylglycerin war die von Schmid [Schmid 1999] entwickelte lipase-katalysierte Zwei-Schritt-Synthese für strukturierte Triglyceride vom Typ ABA [European Patent Application; EP 0 882 797 A2]. In der ersten Reaktionsstufe dieser zweistufigen Umesterung wird in einer Folgereaktion das Substrat Tripalmitin mit Hilfe ein...

Rescue of heart lipoprotein lipase-knockout mice confirms a role for triglyceride in optimal heart metabolism and function.

Science.gov (United States)

Khan, Raffay S; Lin, Yan; Hu, Yunying; Son, Ni-Huiping; Bharadwaj, Kalyani G; Palacios, Carla; Chokshi, Aalap; Ji, Ruiping; Yu, Shuiqing; Homma, Sunichi; Schulze, P Christian; Tian, Rong; Goldberg, Ira J

2013-12-01

Hearts utilize fatty acids as a primary source of energy. The sources of those lipids include free fatty acids and lipoprotein triglycerides. Deletion of the primary triglyceride-hydrolyzing enzyme lipoprotein lipase (LPL) leads to cardiac dysfunction. Whether heart LPL-knockout (hLPL0) mice are compromised due a deficiency in energetic substrates is unknown. To test whether alternative sources of energy will prevent cardiac dysfunction in hLPL0 mice, two different models were used to supply nonlipid energy. 1) hLPL0 mice were crossed with mice transgenically expressing GLUT1 in cardiomyocytes to increase glucose uptake into the heart; this cross-corrected cardiac dysfunction, reduced cardiac hypertrophy, and increased myocardial ATP. 2) Mice were randomly assigned to a sedentary or training group (swimming) at 3 mo of age, which leads to increased skeletal muscle production of lactate. hLPL0 mice had greater expression of the lactate transporter monocarboxylate transporter-1 (MCT-1) and increased cardiac lactate uptake. Compared with hearts from sedentary hLPL0 mice, hearts from trained hLPL0 mice had adaptive hypertrophy and improved cardiac function. We conclude that defective energy intake and not the reduced uptake of fat-soluble vitamins or cholesterol is responsible for cardiac dysfunction in hLPL0 mice. In addition, our studies suggest that adaptations in cardiac metabolism contribute to the beneficial effects of exercise on the myocardium of patients with heart failure.

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

Science.gov (United States)

Gopinath, Subash C. B.; Anbu, Periasamy; Lakshmipriya, Thangavel; Hilda, Azariah

2013-01-01

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. PMID:23865040

MALDI imaging of enzymatic degradation of glycerides by lipase on textile surface

DEFF Research Database (Denmark)

Hall-Andersen, Jonatan; Kaasgaard, Svend G; Janfelt, Christian

2018-01-01

Most modern laundry detergents contain enzymes such as proteases, amylases, and lipases for more efficient removal of stains containing proteins, carbohydrates, and lipids during wash at low temperature. The function of the lipases is to hydrolyse the hydrophobic triglycerides from fats and oils...... stain and simulating washing cycles using well-defined detergents with lipase concentrations ranging between 0 and 0.5ppm. After washing, the textile swatches as well as cryo-sections of the swatches were imaged using MALDI imaging in positive ion mode at pixel sizes of 15-75μm. Similar samples were...... an inhomogeneous presence of diglycerides after lipase treatment both in planar images of the textile surface as well as in cross-sections suggesting a non-uniform enzyme effect or extraction of the lipase reaction products from the textile....

Hemocompatible ɛ-polylysine-heparin microparticles: A platform for detecting triglycerides in whole blood.

Science.gov (United States)

Xu, Tingting; Chi, Bo; Chu, Meilin; Zhang, Qicheng; Zhan, Shuyue; Shi, Rongjia; Xu, Hong; Mao, Chun

2018-01-15

Triglycerides are clinically important marker for atherosclerosis, heart disease and hypertension. Here, a platform for detecting triglycerides in whole blood directly was developed based on hemocompatible ɛ-polylysine-heparin microparticles. The obtained products of ɛ-polylysine-heparin microparticles were characterized by fourier transform infrared (FT-IR) spectra, transmission electron microscopy (TEM) and ζ-potential. Moreover, the blood compatibility of ɛ-polylysine-heparin microparticles was characterized by in vitro coagulation tests, hemolysis assay and whole blood adhesion tests. Considering of uniform particle size, good dispersibility and moderate long-term anticoagulation capability of the microparticles, a Lipase-(ɛ-polylysine-heparin)-glassy carbon electrode (GCE) was constructed to detect triglycerides. The proposed biosensor had good electrocatalytic activity towards triglycerides, in which case the sensitivity was 0.40μAmg -1 dLcm -2 and the detection limit was 4.67mgdL -1 (S/N = 3). Meanwhile, the Lipase-(ɛ-polylysine-heparin)-GCE electrode had strong anti-interference ability as well as a long shelf-life. Moreover, for the detection of triglycerides in whole blood directly, the detection limit was as low as 5.18mgdL -1 . The new constructed platform is suitable for detecting triglycerides in whole blood directly, which provides new analytical systems for clinical illness diagnosis. Copyright © 2017 Elsevier B.V. All rights reserved.

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

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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

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

International Nuclear Information System (INIS)

Hashimoto, Takeshi; Yokokawa, Takumi; Endo, Yuriko; Iwanaka, Nobumasa; Higashida, Kazuhiko; Taguchi, Sadayoshi

2013-01-01

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 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

Fat digestion in the stomach: stability of lingual lipase in the gastric environment.

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Fink, C S; Hamosh, P; Hamosh, M

1984-03-01

Digestion of dietary fat starts in the stomach, where lingual lipase hydrolyzes triglycerides to free fatty acids and partial glycerides at pH 3.0-6.0. Lingual lipase is secreted continuously from lingual serous glands and accumulates in the stomach between meals, when gastric pH is less than 3.0. We have, therefore, examined the resistance of lingual lipase to low pH and its possible protection by dietary components present in the stomach contents. Partially purified rat lingual lipase (7-15 micrograms enzyme protein) was preincubated at 37 degrees C for 10-60 min at pH 1.0-6.0 before incubation for assay of lipolytic activity, hydrolysis of tri-[3H]olein at pH 5.4. The data show that partially purified rat lingual lipase preparations are stable at 37 degrees C in the pH range of 2.5-6.0. Enzyme activity, however, is rapidly and irreversibly lost during preincubation at pH 1.0-2.4 for 10-30 min. Protein (gelatin 1% or albumin 1% or 2.5%) cannot prevent the inactivation of lingual lipase at low pH. The large molecular species (molecular weight greater than 500,000) of lingual lipase (thought to be an aggregate of enzyme with lipids) is slightly more resistant to inactivation than the 46,000 dalton preparation, suggesting that lipids might protect the enzyme from inactivation. Indeed, about 60% of the initial lipase activity is preserved during incubation at pH 2.0 in the presence of 50 mM lecithin or 10 mM triolein. The data indicate that triglycerides which are hydrolyzed by this enzyme as well as phospholipids that are not hydrolyzed can prevent the inactivation of the enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)

G0S2: A small giant controller of lipolysis and adipose-liver fatty acid flux.

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Zhang, Xiaodong; Heckmann, Bradlee L; Campbell, Latoya E; Liu, Jun

2017-10-01

The discovery of adipose triglyceride lipase (ATGL) and its coactivator comparative gene identification-58 (CGI-58) provided a major paradigm shift in the understanding of intracellular lipolysis in both adipocytes and nonadipocyte cells. The subsequent discovery of G0/G1 switch gene 2 (G0S2) as a potent endogenous inhibitor of ATGL revealed a unique mechanism governing lipolysis and fatty acid (FA) availability. G0S2 is highly conserved in vertebrates, and exhibits cyclical expression pattern between adipose tissue and liver that is critical to lipid flux and energy homeostasis in these two tissues. Biochemical and cell biological studies have demonstrated that a direct interaction with ATGL mediates G0S2's inhibitory effects on lipolysis and lipid droplet degradation. In this review we examine evidence obtained from recent in vitro and in vivo studies that lends support to the proof-of-principle concept that G0S2 functions as a master regulator of tissue-specific balance of TG storage vs. mobilization, partitioning of metabolic fuels between adipose and liver, and the whole-body adaptive energy response. This article is part of a Special Issue entitled: Recent Advances in Lipid Droplet Biology edited by Rosalind Coleman and Matthijs Hesselink. Copyright © 2017 Elsevier B.V. All rights reserved.

Fat storage-inducing transmembrane protein 2 is required for normal fat storage in adipose tissue.

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Miranda, Diego A; Kim, Ji-Hyun; Nguyen, Long N; Cheng, Wang; Tan, Bryan C; Goh, Vera J; Tan, Jolene S Y; Yaligar, Jadegoud; Kn, Bhanu Prakash; Velan, S Sendhil; Wang, Hongyan; Silver, David L

2014-04-04

Triglycerides within the cytosol of cells are stored in a phylogenetically conserved organelle called the lipid droplet (LD). LDs can be formed at the endoplasmic reticulum, but mechanisms that regulate the formation of LDs are incompletely understood. Adipose tissue has a high capacity to form lipid droplets and store triglycerides. Fat storage-inducing transmembrane protein 2 (FITM2/FIT2) is highly expressed in adipocytes, and data indicate that FIT2 has an important role in the formation of LDs in cells, but whether FIT2 has a physiological role in triglyceride storage in adipose tissue remains unproven. Here we show that adipose-specific deficiency of FIT2 (AF2KO) in mice results in progressive lipodystrophy of white adipose depots and metabolic dysfunction. In contrast, interscapular brown adipose tissue of AF2KO mice accumulated few but large LDs without changes in cellular triglyceride levels. High fat feeding of AF2KO mice or AF2KO mice on the genetically obese ob/ob background accelerated the onset of lipodystrophy. At the cellular level, primary adipocyte precursors of white and brown adipose tissue differentiated in vitro produced fewer but larger LDs without changes in total cellular triglyceride or triglyceride biosynthesis. These data support the conclusion that FIT2 plays an essential, physiological role in fat storage in vivo.

Effect of sodium-glucose cotransporter 2 (SGLT2) inhibition on weight loss is partly mediated by liver-brain-adipose neurocircuitry.

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Sawada, Yoshikazu; Izumida, Yoshihiko; Takeuchi, Yoshinori; Aita, Yuichi; Wada, Nobuhiro; Li, EnXu; Murayama, Yuki; Piao, Xianying; Shikama, Akito; Masuda, Yukari; Nishi-Tatsumi, Makiko; Kubota, Midori; Sekiya, Motohiro; Matsuzaka, Takashi; Nakagawa, Yoshimi; Sugano, Yoko; Iwasaki, Hitoshi; Kobayashi, Kazuto; Yatoh, Shigeru; Suzuki, Hiroaki; Yagyu, Hiroaki; Kawakami, Yasushi; Kadowaki, Takashi; Shimano, Hitoshi; Yahagi, Naoya

2017-11-04

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have both anti-diabetic and anti-obesity effects. However, the precise mechanism of the anti-obesity effect remains unclear. We previously demonstrated that the glycogen depletion signal triggers lipolysis in adipose tissue via liver-brain-adipose neurocircuitry. In this study, therefore, we investigated whether the anti-obesity mechanism of SGLT2 inhibitor is mediated by this mechanism. Diet-induced obese mice were subjected to hepatic vagotomy (HVx) or sham operation and loaded with high fat diet containing 0.015% tofogliflozin (TOFO), a highly selective SGLT2 inhibitor, for 3 weeks. TOFO-treated mice showed a decrease in fat mass and the effect of TOFO was attenuated in HVx group. Although both HVx and sham mice showed a similar level of reduction in hepatic glycogen by TOFO treatment, HVx mice exhibited an attenuated response in protein phosphorylation by protein kinase A (PKA) in white adipose tissue compared with the sham group. As PKA pathway is known to act as an effector of the liver-brain-adipose axis and activate triglyceride lipases in adipocytes, these results indicated that SGLT2 inhibition triggered glycogen depletion signal and actuated liver-brain-adipose axis, resulting in PKA activation in adipocytes. Taken together, it was concluded that the effect of SGLT2 inhibition on weight loss is in part mediated via the liver-brain-adipose neurocircuitry. Copyright © 2017 Elsevier Inc. All rights reserved.

Fatty Acid Signaling: The New Function of Intracellular Lipases

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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.

Preparation of Oxygen Meter Based Biosensor for Determination of Triglyceride in Serum

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M. BHAMBI

2006-05-01

Full Text Available A method is described for preparation of a dissolved oxygen meter (make Aqualytic, Germany based triglyceride biosensor employing a polyvinyl chloride (PVC membrane bound lipase, glycerol kinase (GK and glycerol-3-phosphate oxidase The biosensor measures dissolved O2 utilized in the oxidation of triglyceride (TG by membrane bound lipase, glycerol kinase (GK and glycerol-3-phosphate oxidase (GPO, which is directly proportional to (TG concentration. The biosensor showed optimum response within 10-15 sec at pH 7.5 and 39.5 ºC. A linear relationship was obtained between the (TG concentration from 5mM to 20mM and oxygen consumed (mg/L. The biosensor was employed for determination of triglyceride in serum. The within and between batch coefficient of variation (CV were < 2.18 % and < 1.7% respectively. The minimum detection limit of the biosensor was 0.35 mM. A study of interference revealed that ascorbic acid, cholesterol and bilirubin caused 13%, 15%, and 12% interference, respectively.The biosensor is portable and can be used outside the laboratory.

Les lipases sont des hydrolases atypiques : principales caractéristiques et applications

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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.

ENZYMATIC BIODIESEL SYNTHESIS FROM ACID OIL USING A LIPASE MIXTURE

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Kelly C. N. R. Pedro

Full Text Available The conventional biodiesel production process has some disadvantages. It is necessary to use refined vegetable oils with low free fatty acids (FFAs content. An alternative route is to use low-cost acid oils in an enzymatic process. The use of lipases allows simultaneous esterification of FFAs and transesterification of triglycerides present in raw material forming alkyl esters. The aim of this work was to study the production of biodiesel using soybean oils with different acid contents (Acid Value of 8.5, 50, 90 and ethanol catalyzed by commercial immobilized lipases (Novozym 435, Lipozyme RM IM and Lipozyme TL IM. A significant decrease of acid value was observed mainly with Novozym 435 and Lipozyme RM IM. The use of a mixture of two immobilized lipases was also investigated to decrease catalyst cost and increase the amount of ester produced. The three commercial immobilized lipases were mixed in a dual system and tested for biodiesel synthesis from acid oil (AV of 8.5, 50 and 90. A positive synergistic effect occurred mainly for Lipozyme TL IM (1,3-specific lipase and Novozym 435 (non-specific lipase blend. The ester content doubled when this lipase mixture was used in ethanolysis of acid oil with AV of 90.

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

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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.

Effect of Global ATGL Knockout on Murine Fasting Glucose Kinetics

NARCIS (Netherlands)

Coelho, M.; Nunes, P.; Mendes, V.M.; Manadas, B.; Heerschap, A.; Jones, J.G.

2015-01-01

Mice deficient in adipose triglyceride lipase (ATGL(-/-)) present elevated ectopic lipid levels but are paradoxically glucose-tolerant. Measurement of endogenous glucose production (EGP) and Cori cycle activity provide insights into the maintenance of glycemic control in these animals. These

Lipase-catalyzed biodiesel synthesis with different acyl acceptors

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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.

Angiopoietin-like 4 promotes intracellular degradation of lipoprotein lipase in adipocytes

NARCIS (Netherlands)

Dijk, W.; Beigneux, Anne P.; Larsson, Mikael; Bensadoun, André; Young, Stephen G.; Kersten, A.H.

2016-01-01

LPL hydrolyzes triglycerides in triglyceride-rich
lipoproteins along the capillaries of heart, skeletal muscle,
and adipose tissue. The activity of LPL is repressed by angiopoietin-
like 4 (ANGPTL4) but the underlying mechanisms
have not been fully elucidated. Our objective was

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

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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...

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

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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). © 2015 FEBS.

Lipoprotein Lipase mRNA expression in different tissues of farm ...

African Journals Online (AJOL)

Lipoprotein lipase (LPL) controls triacylglycerol partitioning between adipose tissues and muscles, so it is important enzyme for fattening of animals .The present work was planned to clarify the use of polymerase chain reaction (PCR) for detection of LPL mRNA expression in different tissues representing internal organs of ...

Simultaneous enzymatic synthesis of FAME and triacetyl glycerol from triglycerides and methyl acetate.

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Usai, E M; Gualdi, E; Solinas, V; Battistel, E

2010-10-01

In the presence of methyl acetate triglycerides such as vegetable oils are transformed simultaneously into the corresponding fatty acid methyl esters and triacetyl glycerol (triacetin). The reaction, catalyzed by lipases, was studied as a function of some critical parameters, such as type of catalyst, enzyme hydration and immobilization support. The aim of the work was to achieve a conversion of the triglyceride as high as possible and to maximize the yield of the triacetin, the reaction end point. It was found that by using the immobilized lipase from Candida antarctica yields as high as 80% of both fatty acid esters and triacetin could be achieved. These results were obtained by carefully controlling the amount of water present in the reaction medium and the hydration level of the enzyme macromolecule. Copyright © 2010 Elsevier Ltd. All rights reserved.

Tumor necrosis factor (cachetin) decreases adipose cell differentiation in primary cell culture

International Nuclear Information System (INIS)

Martin, R.J.; Jones, D.D.; Jewell, D.E.; Hausman, G.J.

1986-01-01

Cachetin has been shown to effect gene product expression in the established adipose cell line 3T3-L1. Expression of messenger RNA for lipoprotein lipase is suppressed in cultured adipocytes. The purpose of this study was to determine the effect of Cachetin on adipose cell differentiation in primary cell culture. Stromalvascular cells obtained from the inguinal fat pad of 4-5 week old Sprague-Dawley rats were grown in culture for two weeks. During the proliferative growth phase all cells were grown on the same medium and labelled with 3 H-thymidine. Cachetin treatment (10 -6 to 10 -10 M) was initiated on day 5, the initial phase of preadipocyte differentiation. Adipocytes and stromal cells were separated using density gradient, and 3 H-thymidine was determined for both cell types. Thymidine incorporation into adipose cells was decreased maximally (∼ 50%) at 10 -10 M. Stromalvascular cells were not influenced at any of the doses tested. Adipose cell lipid content as indicated by oil red-O staining was decreased by Cachetin. Esterase staining by adipose cells treated with Cachetin was increased indicating an increase in intracellular lipase. These studies show that Cachetin has specific effects on primary adipose cell differentiation

Investigations with tritium-labelled glycerol of the triglyceride metabolism in patients

International Nuclear Information System (INIS)

Leonhardt, W.; Julius, U.; Koch, R.; Schulze, J.

1980-01-01

Triglycerides, being components of lipoproteins, are secreted by the liver into the blood and climinated from the blood by adipose and muscle tissue. The kinetics of this metabolic pathway were studied after injection of tritium-labelled glycerol which is incorporated into triglycerides by the liver. The serum triglyceride radioactivity-time curve was analysed with a computer. 99 examinations showed a decrease of the fractional turnover rate and an increase of the turnover rate with the triglyceride level. The test enables to decide whether an increased triglyceride concentration is caued by overproduction or by disturbed climination. (author)

Sympathetic nervous system control of triglyceride metabolism: novel concepts derived from recent studies

NARCIS (Netherlands)

Geerling, Janine J.; Boon, Mariëtte R.; Kooijman, Sander; Parlevliet, Edwin T.; Havekes, Louis M.; Romijn, Johannes A.; Meurs, Illiana M.; Rensen, Patrick C. N.

2014-01-01

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.

Exceptionally elevated triglyceride in severe lipemia retinalis

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Yin HY

2016-10-01

Full Text Available Han Y Yin,1–3 Roberto Warman,2,4 Edward H Suh,2 Anny MS Cheng2,3 1Wayne State University, School of Medicine, Detroit, MI, 2Department of Ophthalmology, Florida International University, Herbert Wertheim College of Medicine, 3Ocular Surface Center, Miami, 4Division of Pediatric Ophthalmology, Nicklaus Children’s Hospital, Miami, FL, USA Purpose: To report a case of successful treatment for severe lipemia retinalis with extreme severe hypertriglyceridemia (sHTG.Design: Observational case report.Observations: A 6-week-old infant with severe lipemia retinalis manifested diffuse creamy retinal vessels complicated with vulvar xanthomas. Extreme sHTG with 185-folds of the normal level was reported. Chromosome microarray and lipid gene sequencing confirmed a homozygous lipoprotein lipase gene coding mutation.Results: Under strict adherence to a high medium-chain triglycerides formula and discontinuation of breast milk, the lipemia retinalis and vulval lesions resolved along with a stable plasma lipid level throughout the follow-up period of 6 months.Conclusion: Strict adherence to a low-fat diet without breast milk appears to be effective in treating infants with severe lipemia retinalis associated with exceptionally high triglycerides. Keywords: hypertriglyceride, infant, lipemia retinalis, lipoprotein lipase gene

Lipoprotein lipase: genetics, lipid uptake, and regulation.

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Merkel, Martin; Eckel, Robert H; Goldberg, Ira J

2002-12-01

Lipoprotein lipase (LPL) regulates the plasma levels of triglyceride and HDL. Three aspects are reviewed. 1) Clinical implications of human LPL gene variations: common mutations and their effects on plasma lipids and coronary heart disease are discussed. 2) LPL actions in the nervous system, liver, and heart: the discussion focuses on LPL and tissue lipid uptake. 3) LPL gene regulation: the LPL promoter and its regulatory elements are described.

GPIHBP1 and Plasma Triglyceride Metabolism.

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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. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

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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.

The g0/g1 switch gene 2 is an important regulator of hepatic triglyceride metabolism.

Science.gov (United States)

Wang, Yinfang; Zhang, Yahui; Qian, Hang; Lu, Juan; Zhang, Zhifeng; Min, Xinwen; Lang, Mingjian; Yang, Handong; Wang, Nanping; Zhang, Peng

2013-01-01

Nonalcoholic fatty liver disease is associated with obesity and insulin resistance. Factors that regulate the disposal of hepatic triglycerides contribute to the development of hepatic steatosis. G0/G1 switch gene 2 (G0S2) is a target of peroxisome proliferator-activated receptors and plays an important role in regulating lipolysis in adipocytes. Therefore, we investigated whether G0S2 plays a role in hepatic lipid metabolism. Adenovirus-mediated expression of G0S2 (Ad-G0S2) potently induced fatty liver in mice. The liver mass of Ad-G0S2-infected mice was markedly increased with excess triglyceride content compared to the control mice. G0S2 did not change cellular cholesterol levels in hepatocytes. G0S2 was found to be co-localized with adipose triglyceride lipase at the surface of lipid droplets. Hepatic G0S2 overexpression resulted in an increase in plasma Low-density lipoprotein (LDL)/Very-Low-density (VLDL) lipoprotein cholesterol level. Plasma High-density lipoprotein (HDL) cholesterol and ketone body levels were slightly decreased in Ad-G0S2 injected mice. G0S2 also increased the accumulation of neutral lipids in cultured HepG2 and L02 cells. However, G0S2 overexpression in the liver significantly improved glucose tolerance in mice. Livers expressing G0S2 exhibited increased 6-(N-(7-nitrobenz-2-oxa-1-3-diazol-4-yl) amino)-6-deoxyglucose uptake compared with livers transfected with control adenovirus. Taken together, our results provide evidence supporting an important role for G0S2 as a regulator of triglyceride content in the liver and suggest that G0S2 may be a molecular target for the treatment of insulin resistance and other obesity-related metabolic disorders.

Fasting Lipoprotein Lipase Protein Levels Can Predict a Postmeal Increment of Triglyceride Levels in Fasting Normohypertriglyceridemic Subjects.

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Tsuzaki, Kokoro; Kotani, Kazuhiko; Yamada, Kazunori; Sakane, Naoki

2016-09-01

Although a postprandial increment in triglyceride (TG) levels is considered to be a risk factor for atherogenesis, tests (e.g., fat load) to assess postprandial changes in TG levels cannot be easily applied to clinical practice. Therefore, fasting markers that predict postprandial TG states are needed to be developed. One current candidate is lipoprotein lipase (LPL) protein, a molecule that hydrides TGs. This study investigated whether fasting LPL levels could predict postprandial TG levels. A total of 17 subjects (11 men, 6 women, mean age 52 ± 11 years) with normotriglyceridemia during fasting underwent the meal test. Several fasting parameters, including LPL, were measured for the area under the curve of postprandial TGs (AUC-TG). The subjects' mean fasting TG level was 1.30 mmol/l, and their mean LPL level was 41.6 ng/ml. The subjects' TG levels increased after loading (they peaked after two postprandial hours). Stepwise multiple regression analysis demonstrated that fasting TG levels were a predictor of the AUC-TG. In addition, fasting LPL mass levels were found to be a predictor of the AUC-TG (β = 0.65, P fasting TG levels. Fasting LPL levels may be useful to predict postprandial TG increment in this population. © 2015 Wiley Periodicals, Inc.

Skeletal muscle PLIN proteins, ATGL and CGI-58, interactions at rest and following stimulated contraction

OpenAIRE

MacPherson, Rebecca E. K.; Ramos, Sofhia V.; Vandenboom, Rene; Roy, Brian D.; Peters, Sandra J.

2013-01-01

Evidence indicates that skeletal muscle lipid droplet-associated proteins (PLINs) regulate lipolysis through protein-protein interactions on the lipid droplet surface. In adipocytes, PLIN1 is thought to regulate lipolysis by directly interacting with comparative gene identification-58 (CGI-58), an activator of adipose triglyceride lipase (ATGL). Upon lipolytic stimulation, PLIN1 is phosphorylated, releasing CGI-58 to fully activate ATGL and initiate triglyceride breakdown. The absence of PLIN...

Involvement of glucocorticoid prereceptor metabolism and signaling in rat visceral adipose tissue lipid metabolism after chronic stress combined with high-fructose diet.

Science.gov (United States)

Bursać, Biljana; Djordjevic, Ana; Veličković, Nataša; Milutinović, Danijela Vojnović; Petrović, Snježana; Teofilović, Ana; Gligorovska, Ljupka; Preitner, Frederic; Tappy, Luc; Matić, Gordana

2018-05-03

Both fructose overconsumption and increased glucocorticoids secondary to chronic stress may contribute to overall dyslipidemia. In this study we specifically assessed the effects and interactions of dietary fructose and chronic stress on lipid metabolism in the visceral adipose tissue (VAT) of male Wistar rats. We analyzed the effects of 9-week 20% high fructose diet and 4-week chronic unpredictable stress, separately and in combination, on VAT histology, glucocorticoid prereceptor metabolism, glucocorticoid receptor subcellular redistribution and expression of major metabolic genes. Blood triglycerides and fatty acid composition were also measured to assess hepatic Δ9 desaturase activity. The results showed that fructose diet increased blood triglycerides and Δ9 desaturase activity. On the other hand, stress led to corticosterone elevation, glucocorticoid receptor activation and decrease in adipocyte size, while phosphoenolpyruvate carboxykinase, adipose tissue triglyceride lipase, FAT/CD36 and sterol regulatory element binding protein-1c (SREBP-1c) were increased, pointing to VAT lipolysis and glyceroneogenesis. The combination of stress and fructose diet was associated with marked stimulation of fatty acid synthase and acetyl-CoA carboxylase mRNA level and with increased 11β-hydroxysteroid dehydrogenase type 1 and hexose-6-phosphate dehydrogenase protein levels, suggesting a coordinated increase in hexose monophosphate shunt and de novo lipogenesis. It however did not influence the level of peroxisome proliferator-activated receptor-gamma, SREBP-1c and carbohydrate responsive element-binding protein. In conclusion, our results showed that only combination of dietary fructose and stress increase glucocorticoid prereceptor metabolism and stimulates lipogenic enzyme expression suggesting that interaction between stress and fructose may be instrumental in promoting VAT expansion and dysfunction. Copyright © 2018 Elsevier B.V. All rights reserved.

Adipocyte triglyceride turnover and lipolysis in lean and overweight subjects.

Science.gov (United States)

Rydén, Mikael; Andersson, Daniel P; Bernard, Samuel; Spalding, Kirsty; Arner, Peter

2013-10-01

Human obesity is associated with decreased triglyceride turnover and impaired lipolysis in adipocytes. We determined whether such defects also occur in subjects with only moderate increase in fat mass. Human abdominal subcutaneous adipose tissue was investigated in healthy, nonobese subjects [body mass index (BMI) > 17 kg/m(2) and BMI lean subjects (P = 0.017) with triglyceride T1/2 of 14 and 9 months, respectively (P = 0.04). Triglyceride age correlated positively with BMI (P = 0.002) but not with adipocyte volume (P = 0.2). Noradrenaline-, isoprenaline- or dibutyryl cyclic AMP-induced lipolysis was inversely correlated with triglyceride age (P maintenance of excess body fat.

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 se...... sequence variants could change the relationship between insulin and IHD....

Defining the Adipose Tissue Proteome of Dairy Cows to Reveal Biomarkers Related to Peripartum Insulin Resistance and Metabolic Status.

Science.gov (United States)

Zachut, Maya

2015-07-02

Adipose tissue is a central regulator of metabolism in dairy cows; however, little is known about the association between various proteins in adipose tissue and the metabolic status of peripartum cows. Therefore, the objectives were to (1) examine total protein expression in adipose tissue of dairy cows and (2) identify biomarkers in adipose that are linked to insulin resistance and to cows' metabolic status. Adipose tissue biopsies were obtained from eight multiparous cows at -17 and +4 days relative to parturition. Proteins were analyzed by intensity-based, label-free, quantitative shotgun proteomics (nanoLC-MS/MS). Cows were divided into groups with insulin-resistant (IR) and insulin-sensitive (IS) adipose according to protein kinase B phosphorylation following insulin stimulation. Cows with IR adipose lost more body weight postpartum compared with IS cows. Differential expression of 143 out of 586 proteins was detected in prepartum versus postpartum adipose. Comparing IR to IS adipose revealed differential expression of 18.9% of the proteins; those related to lipolysis (hormone-sensitive lipase, perilipin, monoglycerol lipase) were increased in IR adipose. In conclusion, we found novel biomarkers related to IR in adipose and to metabolic status that could be used to characterize high-yielding dairy cows that are better adapted to peripartum metabolic stress.

A low-protein, high-carbohydrate diet increases browning in perirenal adipose tissue but not in inguinal adipose tissue.

Science.gov (United States)

Pereira, Mayara P; Ferreira, Laís A A; da Silva, Flávia H S; Christoffolete, Marcelo A; Metsios, George S; Chaves, Valéria E; de França, Suélem A; Damazo, Amílcar S; Flouris, Andreas D; Kawashita, Nair H

2017-10-01

The aim of this study was to evaluate the browning and origin of fatty acids (FAs) in the maintenance of triacylglycerol (TG) storage and/or as fuel for thermogenesis in perirenal adipose tissue (periWAT) and inguinal adipose tissue (ingWAT) of rats fed a low-protein, high-carbohydrate (LPHC) diet. LPHC (6% protein, 74% carbohydrate) or control (C; 17% protein, 63% carbohydrate) diets were administered to rats for 15 d. The tissues were stained with hematoxylin and eosin for histologic analysis. The content of uncoupling protein 1 (UCP1) was determined by immunofluorescence. Levels of T-box transcription factor (TBX1), PR domain containing 16 (PRDM16), adipose triacylglycerol lipase (ATGL), hormone-sensitive lipase, lipoprotein lipase (LPL), glycerokinase, phosphoenolpyruvate carboxykinase (PEPCK), glucose transporter 4, β 3 -adrenergic receptor (AR), β 1 -AR, protein kinase A (PKA), adenosine-monophosphate-activated protein kinase (AMPK), and phospho-AMPK were determined by immunoblotting. Serum fibroblast growth factor 21 (FGF21) was measured using a commercial kit (Student's t tests, P diet increased FGF21 levels by 150-fold. The presence of multilocular adipocytes, combined with the increased contents of UCP1, TBX1, and PRDM16 in periWAT of LPHC-fed rats, suggested the occurrence of browning. The contents of β 1 -AR and LPL were increased in the periWAT. The ingWAT showed higher ATGL and PEPCK levels, phospho-AMPK/AMPK ratio, and reduced β 3 -AR and PKA levels. These findings suggest that browning occurred only in the periWAT and that higher utilization of FAs from blood lipoproteins acted as fuel for thermogenesis. Increased glycerol 3-phosphate generation by glyceroneogenesis increased FAs reesterification from lipolysis, explaining the increased TG storage in the ingWAT. Copyright © 2017 Elsevier Inc. All rights reserved.

Physiologic and genetic evidence links hemopexin to triglycerides in mice and humans.

Science.gov (United States)

Lawson, H A; Zayed, M; Wayhart, J P; Fabbrini, E; Love-Gregory, L; Klein, S; Semenkovich, C F

2017-04-01

Elevated triglycerides predict insulin resistance and vascular disease in obesity, but how the inert triglyceride molecule is related to development of metabolic disease is unknown. To pursue novel potential mediators of triglyceride-associated metabolic disease, we used a forward genetics approach involving inbred mice and translated our findings to human subjects. Hemopexin (HPX) was identified as a differentially expressed gene within a quantitative trait locus associated with serum triglycerides in an F 16 advanced intercross between the LG/J and SM/J strains of mice. Hpx expression was evaluated in both the reproductive fat pads and livers of mice representing three strains, LG/J (n=25), SM/J (n=27) and C57Bl/6J (n=19), on high- and low-fat diets. The effect of altered Hpx expression on adipogenesis was studied in 3T3-L1 cells. Circulating HPX protein along with HPX expression were characterized in subcutaneous white adipose tissue samples obtained from a cohort of metabolically abnormal (n=18) and of metabolically normal (n=24) obese human subjects. We further examined the relationship between HPX and triglycerides in human atherosclerotic plaques (n=18). HPX expression in mouse adipose tissue, but not in liver, was regulated by dietary fat regardless of genetic background. HPX increased in concert with adipogenesis in 3T3-L1 cells, and disruption of its expression impaired adipocyte differentiation. RNAseq data from the adipose tissue of obese humans showed differential expression of HPX based on metabolic disease status (Ptriglycerides in these subjects (r=0.33; P=0.03). HPX was also found in an unbiased proteomic screen of human atherosclerotic plaques and shown to display differential abundance based on the extent of disease and triglyceride content (Ptriglycerides and provide a framework for understanding mechanisms underlying lipid metabolism and metabolic disease.

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

Science.gov (United States)

Salas, Anna; Noé, Véronique; Ciudad, Carlos J; Romero, M Mar; Remesar, Xavier; Esteve, Montserrat

2007-08-28

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. 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 (TNFalpha) values showed overexpression (198%). Short-term treatment with OE affects adipose tissue capacity to extract fatty acids from lipoproteins and to deal with fatty acid transport and metabolism.

Genetics of Triglycerides and the Risk of Atherosclerosis.

Science.gov (United States)

Dron, Jacqueline S; Hegele, Robert A

2017-07-01

Plasma triglycerides are routinely measured with a lipid profile, and elevated plasma triglycerides are commonly encountered in the clinic. The confounded nature of this trait, which is correlated with numerous other metabolic perturbations, including depressed high-density lipoprotein cholesterol (HDL-C), has thwarted efforts to directly implicate triglycerides as causal in atherogenesis. Human genetic approaches involving large-scale populations and high-throughput genomic assessment under a Mendelian randomization framework have undertaken to sort out questions of causality. We review recent large-scale meta-analyses of cohorts and population-based sequencing studies designed to address whether common and rare variants in genes whose products are determinants of plasma triglycerides are also associated with clinical cardiovascular endpoints. The studied loci include genes encoding lipoprotein lipase and proteins that interact with it, such as apolipoprotein (apo) A-V, apo C-III and angiopoietin-like proteins 3 and 4, and common polymorphisms identified in genome-wide association studies. Triglyceride-raising variant alleles of these genes showed generally strong associations with clinical cardiovascular endpoints. However, in most cases, a second lipid disturbance-usually depressed HDL-C-was concurrently associated. While the findings collectively shift our understanding towards a potential causal role for triglycerides, we still cannot rule out the possibilities that triglycerides are a component of a joint phenotype with low HDL-C or that they are but markers of deeper causal metabolic disturbances that are not routinely measured in epidemiological-scale genetic studies.

An update on gene therapy for the treatment of lipoprotein lipase deficiency

Directory of Open Access Journals (Sweden)

Libby AE

2014-05-01

Full Text Available Andrew E Libby, Hong Wang Division of Endocrinology, Metabolism, and Diabetes, School of Medicine, University of Colorado at Denver, Aurora, CO, USA Abstract: Lipoprotein lipase (LPL is responsible for clearance of triglyceride-rich lipoproteins from the blood. Deficiency or defects in this enzyme result in profound hypertriglyceridemia and susceptibility to chronic, life-threatening pancreatitis. Management of LPL deficiency has traditionally been restricted to palliative care and strategies to reduce the risk of pancreatitis, including severe dietary restrictions of fat. Recently, the European Commission approved the first gene therapy treatment in the West to treat this rare disease. Alipogene tiparvovec (Glybera® was granted marketing authorization in November 2012 to treat LPL deficiency in a subset of patients that are at increased risk for pancreatitis. Designed as a one-time treatment, the drug uses adeno-associated virus (AAV1 delivery of transgenic LPL to muscle in patients lacking functional enzyme. Although statistically significant reduction of serum triglycerides was initially observed in trial subjects, this effect was found to be transient, with triglyceride levels eventually rebounding to basal levels by 26 weeks in all participants. Nevertheless, despite the return of triglycerides to pretreatment levels, alipogene tiparvovec was found to have a long-term impact on postprandial chylomicron metabolism by lowering the fraction of triglyceride found in this subset of lipoproteins. Furthermore, the drug led to a clinically significant reduction in the incidence of pancreatitis in LPL-deficient patients. The regulatory approval of alipogene tiparvovec was a historic process and serves as an example of the challenges that future orphan drugs will face. Keywords: lipoprotein lipase deficiency, gene therapy, AAV, chylomicron, pancreatitis

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.

Lipidomic data on lipid droplet triglyceride remodelling associated with protection of breast cancer cells from lipotoxic stress.

Science.gov (United States)

Jarc, Eva; Eichmann, Thomas O; Zimmermann, Robert; Petan, Toni

2018-06-01

The data presented here is related to the research article entitled "Lipid droplets induced by secreted phospholipase A 2 and unsaturated fatty acids protect breast cancer cells from nutrient and lipotoxic stress" by E. Jarc et al., Biochim. Biophys. Acta 1863 (2018) 247-265. Elevated uptake of unsaturated fatty acids and lipid droplet accumulation are characteristic of aggressive cancer cells and have been associated with the cellular stress response. The present study provides lipidomic data on the triacylglycerol (TAG) and phosphatidylcholine (PC) composition of MDA-MB-231 breast cancer cells exposed to docosahexaenoic acid (DHA; 22:6, ω-3). Datasets provide information on the changes in lipid composition induced by depletion of adipose triglyceride lipase (ATGL) and by exogenous addition of secreted phospholipase A 2 (sPLA 2 ) in DHA-treated cells. The presented alterations in lipid composition, mediated by targeting lipid droplet biogenesis and lipolysis, are associated with protection from lipotoxicity and allow further investigation into the role of lipid droplets in the resistance of cancer cells to lipotoxic stress.

Yarrowia lipolytica Lipase 2 Is Stable and Highly Active in Test Meals and Increases Fat Absorption in an Animal Model of Pancreatic Exocrine Insufficiency.

Science.gov (United States)

Aloulou, Ahmed; Schué, Mathieu; Puccinelli, Delphine; Milano, Stéphane; Delchambre, Chantal; Leblond, Yves; Laugier, René; Carrière, Frédéric

2015-12-01

Pancreatic exocrine insufficiency (PEI) reduces pancreatic secretion of digestive enzymes, including lipases. Oral pancreatic enzyme replacement therapy (PERT) with pancreatin produces unsatisfactory results. The lipase 2 produced by the yeast Yarrowia lipolytica (YLLIP2; GenBank: AJ012632) might be used in PERT. We investigated its ability to digest triglycerides in a test meal and its efficacy in reducing fecal fat in an animal model of PEI. YLLIP2 was produced by genetically engineered Y lipolytica and purified from culture media. YLLIP2 or other gastric (LIPF) and pancreatic (PNLIPD) lipases were added to a meal paste containing dietary triglycerides, at a range of pH values (pH 2-7), with and without pepsin or human bile and incubated at 37°C. We collected samples at various time points and measured lipase activities and stabilities. To create an animal model of PEI, steatorrhea was induced by embolization of the exocrine pancreas gland and pancreatic duct ligation in minipigs. The animals were given YLLIP2 (1, 4, 8, 40, or 80 mg/d) or pancreatin (100,000 US Pharmacopeia lipase units/d, controls) for 9 days. We then collected stool samples, measured fat levels, and calculated coefficient of fat absorption (CFA) values. YLLIP2 was highly stable and poorly degraded by pepsin, and had the highest activity of all lipases tested on meal triglyceride at pH 4-7 (pH 6 with bile: 94 ± 34 U/mg; pH 4 without bile: 43 ± 13 U/mg). Only gastric lipase was active and stable at pH 3, whereas YLLIP2 was sensitive to pepsin hydrolysis after pH inactivation. From in vitro test meal experiments, the lipase activity of YLLIP2 (10 mg) was estimated to be equivalent to that of pancreatin (1200 mg; 100,000 US Pharmacopeia units) at pH 6. In PEI minipigs, CFA values increased from 60.1% ± 9.3% before surgery to 90.5% ± 3.2% after administration of 1200 mg pancreatin (P meal triglycerides in a large pH range, with and without bile. Oral administration of milligram amounts of

New ether-functionalized ionic liquids for lipase-catalyzed synthesis of biodiesel.

Science.gov (United States)

Zhao, Hua; Song, Zhiyan; Olubajo, Olarongbe; Cowins, Janet V

2010-09-01

Ionic liquids (ILs) are being explored as solvents for the enzymatic methanolysis of triglycerides. However, most available ILs (especially hydrophobic ones) have poor capability in dissolving lipids, while hydrophilic ILs tend to cause enzyme inactivation. Recently, we synthesized a new type of ether-functionalized ionic liquids (ILs) carrying anions of acetate or formate; they are capable of dissolving a variety of substrates and are also lipase-compatible (Green Chem., 2008, 10, 696-705). In the present study, we carried out the lipase-catalyzed transesterifications of Miglyol oil 812 and soybean oil in these novel ILs. These ILs are capable of dissolving oils at the reaction temperature (50 degrees C); meanwhile, lipases maintained high catalytic activities in these media even in high concentrations of methanol (up to 50% v/v). High conversions of Miglyol oil were observed in mixtures of IL and methanol (70/30, v/v) when the reaction was catalyzed by a variety of lipases and different enzyme preparations (free and immobilized), especially with the use of two alkylammonium ILs 2 and 3. The preliminary study on the transesterification of soybean oil in IL/methanol mixtures further confirms the potential of using oil-dissolving and lipase-stabilizing ILs in the efficient production of biodiesels.

White adipose tissue: Getting nervous

NARCIS (Netherlands)

Fliers, E.; Kreier, F.; Voshol, P. J.; Havekes, L. M.; Sauerwein, H. P.; Kalsbeek, A.; Buijs, R. M.; Romijn, J. A.

2003-01-01

Neuroendocrine research has altered the traditional perspective of white adipose tissue (WAT) as a passive store of triglycerides. In addition to fatty acids, WAT produces many hormones and can therefore be designated as a traditional endocrine gland actively participating in the integrative

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.

Contribution of novel ATGL missense mutations to the clinical phenotype of NLSD-M: a strikingly low amount of lipase activity may preserve cardiac function.

Science.gov (United States)

Tavian, Daniela; Missaglia, Sara; Redaelli, Chiara; Pennisi, Elena M; Invernici, Gloria; Wessalowski, Ruediger; Maiwald, Robert; Arca, Marcello; Coleman, Rosalind A

2012-12-15

The lack of adipose triglyceride lipase (ATGL), a patatin-like phospholipase domain-containing enzyme that hydrolyzes fatty acids from triacylglycerol (TAG) stored in multiple tissues, causes the autosomal recessive disorder neutral lipid storage disease with myopathy (NLSD-M). In two families of Lebanese and Italian origin presenting with NLSD-M, we identified two new missense mutations in highly conserved regions of ATGL (p.Arg221Pro and p.Asn172Lys) and a novel nonsense mutation (p.Trp8X). The Lebanese patients harbor homozygous p.Arg221Pro, whereas the Italian patients are heterozygotes for p.Asn172Lys and the p.Trp8X mutation. The p.Trp8X mutation results in a complete absence of ATGL protein, while the p.Arg221Pro and p.Asn172Lys mutations result in proteins with minimal lipolytic activity. Although these mutations did not affect putative catalytic residues or the lipid droplet (LD)-binding domain of ATGL, cytosolic LDs accumulated in cultured skin fibroblasts from the patients. The missense mutations might destabilize a random coil (p.Asn172Lys) or a helix (p.Arg221Pro) structure within or proximal to the patatin domain of the lipase, thereby interfering with the enzyme activity, while leaving intact the residues required to localize the protein to LDs. Overexpressing wild-type ATGL in one patient's fibroblasts corrected the metabolic defect and effectively reduced the number and area of cellular LDs. Despite the poor lipase activity in vitro, the Lebanese siblings have a mild myopathy and not clinically evident myocardial dysfunction. The patients of Italian origin show a late-onset and slowly progressive skeletal myopathy. These findings suggest that a small amount of correctly localized lipase activity preserves cardiac function in NLSD-M.

The VLDL receptor plays a major role in chylomicron metabolism by enhancing LPL-mediated triglyceride hydrolysis

NARCIS (Netherlands)

Goudriaan, Jeltje R.; Espirito Santo, Sonia M. S.; Voshol, Peter J.; Teusink, Bas; van Dijk, Ko Willems; van Vlijmen, Bart J. M.; Romijn, Johannes A.; Havekes, Louis M.; Rensen, Patrick C. N.

2004-01-01

The VLDL receptor (VLDLr) is involved in tissue delivery of VLDL-triglyceride (TG)-derived FFA by facilitating the expression of lipoprotein lipase (LPL). However, vldlr-/- mice do not show altered plasma lipoprotein levels, despite reduced LPL expression. Because LPL activity is crucial in

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...

Effects of dietary heme iron and exercise training on abdominal fat accumulation and lipid metabolism in high-fat diet-fed mice.

Science.gov (United States)

Katsumura, Masanori; Takagi, Shoko; Oya, Hana; Tamura, Shohei; Saneyasu, Takaoki; Honda, Kazuhisa; Kamisoyama, Hiroshi

2017-08-01

Animal by-products can be recycled and used as sources of essential nutrients. Water-soluble heme iron (WSHI), a functional food additive for supplementing iron, is produced by processing animal blood. In this study, we investigated the effects of dietary supplementation of 3% WSHI and exercise training for 4 weeks on the accumulation of abdominal fat and lipid metabolism in mice fed high-fat diet. Exercise-trained mice had significantly less perirenal adipose tissue, whereas WSHI-fed mice tended to have less epididymal adipose tissue. In addition, total weight of abdominal adipose tissues was significantly decreased in the Exercise + WSHI group. Dietary WSHI significantly increased the messenger RNA (mRNA) levels of lipoprotein lipase and hormone-sensitive lipase. WSHI-fed mice also tended to show increased mRNA levels of adipose triglyceride lipase in their epididymal adipose tissue. Dietary WSHI also significantly decreased the mRNA levels of fatty acid oxidation-related enzymes in the liver, but did not influence levels in the Gastrocnemius muscle. Exercise training did not influence the mRNA levels of lipid metabolism-related enzymes in the epididymal adipose tissue, liver or the Gastrocnemius muscle. These findings suggest that the accumulation of abdominal fat can be efficiently decreased by the combination of dietary WSHI and exercise training in mice fed high-fat diet. © 2016 Japanese Society of Animal Science.

Inhibition of Intracellular Triglyceride Lipolysis Suppresses Cold-Induced Brown Adipose Tissue Metabolism and Increases Shivering in Humans.

Science.gov (United States)

Blondin, Denis P; Frisch, Frédérique; Phoenix, Serge; Guérin, Brigitte; Turcotte, Éric E; Haman, François; Richard, Denis; Carpentier, André C

2017-02-07

Indirect evidence from human studies suggests that brown adipose tissue (BAT) thermogenesis is fueled predominantly by fatty acids hydrolyzed from intracellular triglycerides (TGs). However, no direct experimental evidence to support this assumption currently exists in humans. The aim of this study was to determine the role of intracellular TG in BAT thermogenesis, in cold-exposed men. Using positron emission tomography with 11 C-acetate and 18 F-fluorodeoxyglucose, we showed that oral nicotinic acid (NiAc) administration, an inhibitor of intracellular TG lipolysis, suppressed the cold-induced increase in BAT oxidative metabolism and glucose uptake, despite no difference in BAT blood flow. There was a commensurate increase in shivering intensity and shift toward a greater reliance on glycolytic muscle fibers without modifying total heat production. Together, these findings show that intracellular TG lipolysis is critical for BAT thermogenesis and provides experimental evidence for a reciprocal role of BAT thermogenesis and shivering in cold-induced thermogenesis in humans. Copyright © 2017 Elsevier Inc. All rights reserved.

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.

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.

Triglyceride content in remnant lipoproteins is significantly increased after food intake and is associated with plasma lipoprotein lipase.

Science.gov (United States)

Nakajima, Katsuyuki; Tokita, Yoshiharu; Sakamaki, Koji; Shimomura, Younosuke; Kobayashi, Junji; Kamachi, Keiko; Tanaka, Akira; Stanhope, Kimber L; Havel, Peter J; Wang, Tao; Machida, Tetsuo; Murakami, Masami

2017-02-01

Previous large population studies reported that non-fasting plasma triglyceride (TG) reflect a higher risk for cardiovascular disease than TG in the fasting plasma. This is suggestive of the presence of higher concentration of remnant lipoproteins (RLP) in postprandial plasma. TG and RLP-TG together with other lipids, lipoproteins and lipoprotein lipase (LPL) in both fasting and postprandial plasma were determined in generally healthy volunteers and in patients with coronary artery disease (CAD) after consuming a fat load or a more typical moderate meal. RLP-TG/TG ratio (concentration) and RLP-TG/RLP-C ratio (particle size) were significantly increased in the postprandial plasma of both healthy controls and CAD patients compared with those in fasting plasma. LPL/RLP-TG ratio demonstrated the interaction correlation between RLP concentration and LPL activity The increased RLP-TG after fat consumption contributed to approximately 90% of the increased plasma TG, while approximately 60% after a typical meal. Plasma LPL in postprandial plasma was not significantly altered after either type of meal. Concentrations of RLP-TG found in the TG along with its particle size are significantly increased in postprandial plasma compared with fasting plasma. Therefore, non-fasting TG determination better reflects the presence of higher RLP concentrations in plasma. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

PDHK-2 deficiency is associated with attenuation of lipase-mediated fat consumption for the increased survival of Caenorhabditis elegans dauers.

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Sunhee Kim

Full Text Available In Caenorhabditis elegans, slow fat consumption has been suggested to contribute to the extension of the survival rate during nutritionally adverse conditions. Here, we investigated the potential role of pyruvate dehydrogenase kinase (PDHK-2, the C. elegans homolog of mammalian PDK, effects on fat metabolism under nutritional conditions. PDHK-2 was expressed at low levels under well-fed conditions but was highly induced during long-term starvation and in the dauer state. This increase in pdhk-2 expression was regulated by both DAF-16 and NHR-49. Dauer-specific induction of PDHK-2 was abolished upon entry into the post-dauer stage. Interestingly, in the long-term dauer state, stored fat levels were higher in daf-2(e1370;pdhk-2 double mutants than in daf-2(e1370, suggesting a positive relationship between PDHK-2 activity and fat consumption. PDHK-2 deficiency has been shown to lead to greater preservation of residual fats, which would be predicted to contribute to survival during the dauer state. A test of this prediction showed that the survival rates of daf-2(e1370;pdhk-2(tm3075 and daf-2(e1370;pdhk-2(tm3086 double mutants were higher than that of daf-2(e1370, suggesting that loss of either the ATP-binding domain (tm3075 or branched chain keto-acid dehydrogenase kinase domain (tm3086 of PDHK-2 leads to reduced fat consumption and thus favors increased dauer survival. This attenuated fat consumption in the long-term dauer state of C. elegans daf-2 (e1370;pdhk-2 mutants was associated with concomitant down-regulation of the lipases ATGL (adipose triglyceride lipase, HSL (hormone-sensitive lipase, and C07E3.9 (phospholipase. In contrast, PDHK-2 overexpression in wild-type starved worms induced lipase expression and promoted abnormal dauer formation. Thus, we propose that PDHK-2 serves as a molecular bridge, connecting fat metabolism and survival under nutritionally adverse conditions in C. elegans.

Toward the Establishment of Standardized In Vitro Tests for Lipid-Based Formulations. 5. Lipolysis of Representative Formulations by Gastric Lipase

DEFF Research Database (Denmark)

Bakala-N'Goma, Jean-Claude; Williams, Hywel D.; Sassene, Philip J.

2015-01-01

Purpose Lipid-based formulations (LBF) are substrates for digestive lipases and digestion can significantly alter their properties and potential to support drug absorption. LBFs have been widely examined for their behaviour in the presence of pancreatic enzymes. Here, the impact of gastric lipase...... on the digestion of representative formulations from the Lipid Formulation Classification System has been investigated. Methods The pHstat technique was used to measure the lipolysis by recombinant dog gastric lipase (rDGL) of eight LBFs containing either medium (MC) or long (LC) chain triglycerides and a range...

Kinesin-dependent mechanism for controlling triglyceride secretion from the liver.

Science.gov (United States)

Rai, Priyanka; Kumar, Mukesh; Sharma, Geetika; Barak, Pradeep; Das, Saumitra; Kamat, Siddhesh S; Mallik, Roop

2017-12-05

Despite massive fluctuations in its internal triglyceride content, the liver secretes triglyceride under tight homeostatic control. This buffering function is most visible after fasting, when liver triglyceride increases manyfold but circulating serum triglyceride barely fluctuates. How the liver controls triglyceride secretion is unknown, but is fundamentally important for lipid and energy homeostasis in animals. Here we find an unexpected cellular and molecular mechanism behind such control. We show that kinesin motors are recruited to triglyceride-rich lipid droplets (LDs) in the liver by the GTPase ARF1, which is a key activator of lipolysis. This recruitment is activated by an insulin-dependent pathway and therefore responds to fed/fasted states of the animal. In fed state, ARF1 and kinesin appear on LDs, consequently transporting LDs to the periphery of hepatocytes where the smooth endoplasmic reticulum (sER) is present. Because the lipases that catabolize LDs in hepatocytes reside on the sER, LDs can now be catabolized efficiently to provide triglyceride for lipoprotein assembly and secretion from the sER. Upon fasting, insulin is lowered to remove ARF1 and kinesin from LDs, thus down-regulating LD transport and sER-LD contacts. This tempers triglyceride availabiity for very low density lipoprotein assembly and allows homeostatic control of serum triglyceride in a fasted state. We further show that kinesin knockdown inhibits hepatitis-C virus replication in hepatocytes, likely because translated viral proteins are unable to transfer from the ER to LDs. Copyright © 2017 the Author(s). Published by PNAS.

Obesity resistance and multiple mechanisms of triglyceride synthesis in mice lacking Dgat.

Science.gov (United States)

Smith, S J; Cases, S; Jensen, D R; Chen, H C; Sande, E; Tow, B; Sanan, D A; Raber, J; Eckel, R H; Farese, R V

2000-05-01

Triglycerides (or triacylglycerols) represent the major form of stored energy in eukaryotes. Triglyceride synthesis has been assumed to occur primarily through acyl CoA:diacylglycerol transferase (Dgat), a microsomal enzyme that catalyses the final and only committed step in the glycerol phosphate pathway. Therefore, Dgat has been considered necessary for adipose tissue formation and essential for survival. Here we show that Dgat-deficient (Dgat-/-) mice are viable and can still synthesize triglycerides. Moreover, these mice are lean and resistant to diet-induced obesity. The obesity resistance involves increased energy expenditure and increased activity. Dgat deficiency also alters triglyceride metabolism in other tissues, including the mammary gland, where lactation is defective in Dgat-/- females. Our findings indicate that multiple mechanisms exist for triglyceride synthesis and suggest that the selective inhibition of Dgat-mediated triglyceride synthesis may be useful for treating obesity.

Efficient production of biodiesel from waste grease: one-pot esterification and transesterification with tandem lipases.

Science.gov (United States)

Yan, Jinyong; Li, Aitao; Xu, Yi; Ngo, Thao P N; Phua, Szechao; Li, Zhi

2012-11-01

A novel concept and efficient method for producing biodiesel (FAME) from grease (15-40wt% free fatty acid, FFA) were developed by using tandem lipases for one-pot esterification of FFA and transesterification of triglyceride with methanol in a solvent-free system. Combining immobilized Candida antarctica lipase B (CALB) (Novozyme 435) favoring the esterification and immobilized Thermomyces lanuginosus lipase (TLL) (Lipozyme TLIM) preferring the transesterification at 2:8 (wt/wt) gave FAME in 80% yield, being better than that with Novozyme 435 or Lipozyme TLIM. Recombinant Escherichia coli (Calb/Tll) co-expressing CALB and TLL was engineered as a more efficient tandem-lipases system. Using wet or dry cells (4wt%) gave FAME in 87% or 95% yield, which is much better than that with E. coli cells expressing either CALB or TLL alone. Cells of E. coli (Calb/Tll) were recycled for five times and retained 75% productivity, thus being practical for producing biodiesel from grease. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mechanisms of triglyceride metabolism in patients with bile acid diarrhea.

Science.gov (United States)

Sagar, Nidhi Midhu; McFarlane, Michael; Nwokolo, Chuka; Bardhan, Karna Dev; Arasaradnam, Ramesh Pulendran

2016-08-14

Bile acids (BAs) are essential for the absorption of lipids. BA synthesis is inhibited through intestinal farnesoid X receptor (FXR) activity. BA sequestration is known to influence BA metabolism and control serum lipid concentrations. Animal data has demonstrated a regulatory role for the FXR in triglyceride metabolism. FXR inhibits hepatic lipogenesis by inhibiting the expression of sterol regulatory element binding protein 1c via small heterodimer primer activity. Conversely, FXR promotes free fatty acids oxidation by inducing the expression of peroxisome proliferator-activated receptor α. FXR can reduce the expression of microsomal triglyceride transfer protein, which regulates the assembly of very low-density lipoproteins (VLDL). FXR activation in turn promotes the clearance of circulating triglycerides by inducing apolipoprotein C-II, very low-density lipoproteins receptor (VLDL-R) and the expression of Syndecan-1 together with the repression of apolipoprotein C-III, which increases lipoprotein lipase activity. There is currently minimal clinical data on triglyceride metabolism in patients with bile acid diarrhoea (BAD). Emerging data suggests that a third of patients with BAD have hypertriglyceridemia. Further research is required to establish the risk of hypertriglyceridaemia in patients with BAD and elicit the mechanisms behind this, allowing for targeted treatment.

One-Step Partially Purified Lipases (ScLipA and ScLipB from Schizophyllum commune UTARA1 Obtained via Solid State Fermentation and Their Applications

Directory of Open Access Journals (Sweden)

Yew Chee Kam

2017-12-01

Full Text Available Lipases with unique characteristics are of value in industrial applications, especially those targeting cost-effectiveness and less downstream processes. The aims of this research were to: (i optimize the fermentation parameters via solid state fermentation (SSF; and (ii study the performance in hydrolysis and esterification processes of the one-step partially purified Schizophyllum commune UTARA1 lipases. Lipase was produced by cultivating S. commune UTARA1 on sugarcane bagasse (SB with used cooking oil (UCO via SSF and its production was optimized using Design-Expert® 7.0.0. Fractions 30% (ScLipA and 70% (ScLipB which contained high lipase activity were obtained by stepwise (NH42SO4 precipitation. Crude fish oil, coconut oil and butter were used to investigate the lipase hydrolysis capabilities by a free glycerol assay. Results showed that ScLipA has affinities for long, medium and short chain triglycerides, as all the oils investigated were degraded, whereas ScLipB has affinities for long chain triglycerides as it only degrades crude fish oil. During esterification, ScLipA was able to synthesize trilaurin and triacetin. Conversely, ScLipB was specific towards the formation of 2-mono-olein and triacetin. From the results obtained, it was determined that ScLipA and ScLipB are sn-2 regioselective lipases. Hence, the one-step partial purification strategy proved to be feasible for partial purification of S. commune UTARA1 lipases that has potential use in industrial applications.

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.

Lipase biofilm deposited by Matrix Assisted Pulsed Laser Evaporation technique

International Nuclear Information System (INIS)

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

2015-01-01

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

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.

Lipid composition of hepatic and adipose tissues from normal cats and from cats with idiopathic hepatic lipidosis.

Science.gov (United States)

Hall, J A; Barstad, L A; Connor, W E

1997-01-01

The purpose of this study was to characterize the lipid classes in hepatic and adipose tissues from cats with idiopathic hepatic lipidosis (IHL). Concentrations of triglyceride, phospholipid phosphorus, and free and total cholesterol were determined in lipid extracts of liver homogenates from 5 cats with IHL and 5 healthy control cats. Total fatty acid composition of liver and adipose tissue was also compared. Triglyceride accounted for 34% of liver by weight in cats with IHL (338 +/- 38 mg/g wet liver) versus 1% in control cats (9.9 +/- 1.0 mg/g wet liver, P hepatic tissue in the 2 groups differed; palmitate was higher (19.5 +/- 1.1% of total fatty acids in cats with IHL versus 9.2 +/- 2.7% in controls, P hepatic triglyceride in cats with IHL is the mobilization of fatty acids from adipose tissue.

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

Science.gov (United States)

Jessen, Niels; Nielsen, Thomas S; Vendelbo, Mikkel H; Viggers, Rikke; Støen, Ole-Gunnar; Evans, Alina; Frøbert, Ole

2016-04-01

Prior to hibernation, the brown bear (Ursus arctos) exhibits unparalleled weight gain. Unlike humans, weight gain in bears is associated with lower levels of circulating free fatty acids (FFA) and increased insulin sensitivity. Understanding how free-ranging brown bears suppress lipolysis when 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 not differ between seasons, but in contrast, the expression of ATGL coactivator Comparative gene identification-58 (CGI-58) was lower in summer. In addition, the expression of the negative regulators of lipolysis, G0S2 and cell-death inducing DNA fragmentation factor-a-like effector (CIDE)C markedly 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. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Effect of functional sympathetic nervous system impairment of the liver and abdominal visceral adipose tissue on circulating triglyceride-rich lipoproteins.

Science.gov (United States)

La Fountaine, Michael F; Cirnigliaro, Christopher M; Kirshblum, Steven C; McKenna, Cristin; Bauman, William A

2017-01-01

Interruption of sympathetic innervation to the liver and visceral adipose tissue (VAT) in animal models has been reported to reduce VAT lipolysis and hepatic secretion of very low density lipoprotein (VLDL) and concentrations of triglyceride-rich lipoprotein particles. Whether functional impairment of sympathetic nervous system (SNS) innervation to tissues of the abdominal cavity reduce circulating concentrations of triglyceride (TG) and VLDL particles (VLDL-P) was tested in men with spinal cord injury (SCI). One hundred-three non-ambulatory men with SCI [55 subjects with neurologic injury at or proximal to the 4th thoracic vertebrae (↑T4); 48 subjects with SCI at or distal to the 5th thoracic vertebrae (↓T5)] and 53 able-bodied (AB) subjects were studied. Fasting blood samples were obtained for determination of TG, VLDL-P concentration by NMR spectroscopy, serum glucose by autoanalyzer, and plasma insulin by radioimmunoassay. VAT volume was determined by dual energy x-ray absorptiometry imaging with calculation by a validated proprietary software package. Significant group main effects for TG and VLDL-P were present; post-hoc tests revealed that serum TG concentrations were significantly higher in ↓T5 group compared to AB and ↑T4 groups [150±9 vs. 101±8 (plipoproteins (i.e., TG or Large VLDL-P) and VAT volume or HOMA-IR was significant only in the ↓T5 group. Despite a similar VAT volume and insulin resistance in both SCI groups, the ↓T5 group had significantly higher serum TG and VLDL-P values than that observed in the ↑T4 and the AB control groups. Thus, level of injury is an important determinate of the concentration of circulating triglyceride rich lipoproteins, which may play a role in the genesis of cardiometabolic dysfunction.

The ANGPTL3-4-8 model, a molecular mechanism for triglyceride trafficking.

Science.gov (United States)

Zhang, Ren

2016-04-01

Lipoprotein lipase (LPL) is a rate-limiting enzyme for hydrolysing circulating triglycerides (TG) into free fatty acids that are taken up by peripheral tissues. Postprandial LPL activity rises in white adipose tissue (WAT), but declines in the heart and skeletal muscle, thereby directing circulating TG to WAT for storage; the reverse is true during fasting. However, the mechanism for the tissue-specific regulation of LPL activity during the fed-fast cycle has been elusive. Recent identification of lipasin/angiopoietin-like 8 (Angptl8), a feeding-induced hepatokine, together with Angptl3 and Angptl4, provides intriguing, yet puzzling, insights, because all the three Angptl members are LPL inhibitors, and the deficiency (overexpression) of any one causes hypotriglyceridaemia (hypertriglyceridaemia). Then, why does nature need all of the three? Our recent data that Angptl8 negatively regulates LPL activity specifically in cardiac and skeletal muscles suggest an Angptl3-4-8 model: feeding induces Angptl8, activating the Angptl8-Angptl3 pathway, which inhibits LPL in cardiac and skeletal muscles, thereby making circulating TG available for uptake by WAT, in which LPL activity is elevated owing to diminished Angptl4; the reverse is true during fasting, which suppresses Angptl8 but induces Angptl4, thereby directing TG to muscles. The model suggests a general framework for how TG trafficking is regulated. © 2016 The Authors.

Proteinuria and lipoprotein lipase activity in Miniature Schnauzer dogs with and without hypertriglyceridemia.

Science.gov (United States)

Furrow, E; Jaeger, J Q; Parker, V J; Hinchcliff, K W; Johnson, S E; Murdoch, S J; de Boer, I H; Sherding, R G; Brunzell, J D

2016-06-01

Spontaneous hyperlipidemia in rats causes glomerular disease. Idiopathic hypertriglyceridemia (HTG) is prevalent in Miniature Schnauzers, but its relationship with proteinuria is unknown. Decreased activity of major lipid metabolism enzymes, lipoprotein lipase (LPL) and hepatic lipase (HL), may play a role in the cyclic relationship between hyperlipidemia and proteinuria. These enzymes have also not been previously investigated in Miniature Schnauzers. The aims of this study were to determine the relationship between HTG and proteinuria in Miniature Schnauzers and to measure LPL and HL activities in a subset of dogs. Fifty-seven Miniature Schnauzers were recruited (34 with and 23 without HTG). Fasting serum triglyceride concentrations and urine protein-to-creatinine ratios (UPC) were measured in all dogs, and LPL and HL activities were determined in 17 dogs (8 with and 9 without HTG). There was a strong positive correlation between triglyceride concentration and UPC (r = 0.77-0.83, P Schnauzers and could be due to lipid-induced glomerular injury. Reduced LPL activity may contribute to the severity of HTG, but further assay validation is required. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pvu-II RFLP at the human lipoprotein lipase (LPL) gene locus

Energy Technology Data Exchange (ETDEWEB)

Li, S; Oka, K; Galton, D; Stocks, J

1988-03-25

Human lipoprotein lipase (LPL) cDNA, 1.6 Kbp, was isolated from human adipose cDNA library and subcloned into Bam HI site of pIB131. Pvu-II identifies a two allele polymorphism with bands at 7.0 Kb, 4.4 Kb and 2.5 Kb. The frequency was studied in 34 caucasians. The gene was assigned to 8p22. Co-dominant inheritance was demonstrated in a 2 generation family.

Solvent Flux Method (SFM): A Case Study of Water Access to Candida antarctica Lipase B.

Science.gov (United States)

Benson, Sven P; Pleiss, Jürgen

2014-11-11

The solvent flux method (SFM) was developed to comprehensively characterize the influx of solvent molecules from the solvent environment into the active site of a protein in the framework of molecular dynamics simulations. This was achieved by introducing a solvent concentration gradient as well as partially reorienting and rescaling the velocity vector of all solvent molecules contained within a spherical volume enclosing the protein, thus inducing an accelerated solvent influx toward the active site. In addition to the detection of solvent access pathway within the protein structure, it is hereby possible to identify potential amino acid positions relevant to solvent-related enzyme engineering with high statistical significance. The method is particularly aimed at improving the reverse hydrolysis reaction rates in nonaqueous media. Candida antarctica lipase B (CALB) binds to a triglyceride-water interface with its substrate entrance channel oriented toward the hydrophobic substrate interface. The lipase-triglyceride-water system served as a model system for SFM to evaluate the influx of water molecules to the active site. As a proof of principle for SFM, a previously known water access pathway in CALB was identified as the primary water channel. In addition, a secondary water channel and two pathways for water access which contribute to water leakage between the protein and the triglyceride-water interface were identified.

Purification and substrate specificity of Staphylococcus hyicus lipase.

Science.gov (United States)

van Oort, M G; Deveer, A M; Dijkman, R; Tjeenk, M L; Verheij, H M; de Haas, G H; Wenzig, E; Götz, F

1989-11-28

The Staphylococcus hyicus lipase gene has been cloned and expressed in Staphylococcus carnosus. From the latter organism the enzyme was secreted into the medium as a protein with an apparent molecular mass of 86 kDa. This protein was purified, and the amino-terminal sequence showed that the primary gene product was indeed cleaved at the proposed signal peptide cleavage site. The protein was purified from large-scale preparations after tryptic digestion. This limited proteolysis reduced the molecular mass to 46 kDa and increased the specific activity about 3-fold. Although the enzyme had a low specific activity in the absence of divalent cations, the activity increased about 40-fold in the presence of Sr2+ or Ca2+ ions. The purified lipase has a broad substrate specificity. The acyl chains were removed from the primary and secondary positions of natural neutral glycerides and from a variety of synthetic glyceride analogues. Thus triglycerides were fully hydrolyzed to free fatty acid and glycerol. The enzyme hydrolyzed naturally occurring phosphatidylcholines, their synthetic short-chain analogues, and lysophospholipids to free fatty acids and water-soluble products. The enzyme had a 2-fold higher activity on micelles of short-chain D-lecithins than on micelles composed of the L-isomers. Thus the enzyme from S. hyicus has lipase activity and also high phospholipase A and lysophospholipase activity.

Transesterification of waste cooking oil by an organic solvent-tolerant alkaline lipase from Streptomyces sp. CS273.

Science.gov (United States)

Mander, Poonam; Yoo, Hah-Young; Kim, Seung Wook; Choi, Yun Hee; Cho, Seung Sik; Yoo, Jin Cheol

2014-02-01

The aim of this present study was to produce a microbial enzyme that can potentially be utilized for the enzymatic transesterification of waste cooking oil. To that end, an extracellular lipase was isolated and purified from the culture broth of Streptomyces sp. CS273. The molecular mass of purified lipase was estimated to be 36.55 kDa by SDS PAGE. The optimum lipolytic activity was obtained at alkaline pH 8.0 to 8.5 and temperature 40 °C, while the enzyme was stable in the pH range 7.0 ∼ 9.0 and at temperature ≤40 °C. The lipase showed highest hydrolytic activity towards p-nitrophenyl myristate (C14). The lipase activity was enhanced by several salts and detergents including NaCl, MnSo₄, and deoxy cholic acid, while phenylmethylsulfonyl fluoride at concentration 10 mM inhibited the activity. The lipase showed tolerance towards different organic solvents including ethanol and methanol which are commonly used in transesterification reactions to displace alcohol from triglycerides (ester) contained in renewable resources to yield fatty acid alkyl esters known as biodiesel. Applicability of the lipase in transesterification of waste cooking oil was confirmed by gas chromatography mass spectrometry analysis.

The Effects of Smoking Cessation on Visceral Adiposity Index Levels

African Journals Online (AJOL)

2018-06-11

Jun 11, 2018 ... mass index (BMI), and high‑density lipoprotein cholesterol levels .... used to determine the relationship between not normally .... monoxide; VAI=Visceral adiposity index; TG=Triglyceride; HDL‑cholesterol=High density ...

Association of faecal elastase 1 with non-fasting triglycerides in type 2 diabetes.

Science.gov (United States)

Rathmann, Wolfgang; Haastert, Burkhard; Oscarsson, Jan; Berglind, Niklas; Lindkvist, Björn; Wareham, Nicholas J

2016-01-01

Intestinal absorption of esterified fatty acids depends on exocrine pancreatic function and influences plasma triglycerides levels. The aim was to investigate the association of reduced exocrine pancreatic function (low fecal elastase-1; FE1) with plasma triglycerides in type 2 diabetes and controls without diabetes. FE1 (μg/g stool) and non-fasting plasma triglyceride measurements were undertaken in 544 type 2 diabetes patients (age: 63 ± 8 years) randomly selected from diabetes registers in Cambridgeshire (UK), and 544 matched controls (age, sex, practice) without diabetes. Linear regression models were fitted using FE1 as dependent and log-triglycerides as independent variable adjusting for sex, age, body mass index, alcohol consumption, serum lipase, HbA1c, and smoking. FE1 concentrations were lower (mean ± SD: 337 ± 204 vs. 437 ± 216 μg/g, p triglycerides were higher (geometric mean */: standard deviation factor: 2.2*/:1.9 vs. 1.6*/:1.8 mmol/l, p triglycerides was associated with 4.5 μg/g higher FE1 concentrations (p triglycerides (significant only in controls). Non-fasting triglycerides were positively related to FE1 in both type 2 diabetes and controls suggesting that impairment of exocrine pancreas function is influencing plasma triglycerides. Marked loss of exocrine pancreatic function had the opposite effect, resulting in higher levels of plasma triglycerides. Copyright © 2016 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Mechanisms of triglyceride metabolism in patients with bile acid diarrhea

Science.gov (United States)

Sagar, Nidhi Midhu; McFarlane, Michael; Nwokolo, Chuka; Bardhan, Karna Dev; Arasaradnam, Ramesh Pulendran

2016-01-01

Bile acids (BAs) are essential for the absorption of lipids. BA synthesis is inhibited through intestinal farnesoid X receptor (FXR) activity. BA sequestration is known to influence BA metabolism and control serum lipid concentrations. Animal data has demonstrated a regulatory role for the FXR in triglyceride metabolism. FXR inhibits hepatic lipogenesis by inhibiting the expression of sterol regulatory element binding protein 1c via small heterodimer primer activity. Conversely, FXR promotes free fatty acids oxidation by inducing the expression of peroxisome proliferator-activated receptor α. FXR can reduce the expression of microsomal triglyceride transfer protein, which regulates the assembly of very low-density lipoproteins (VLDL). FXR activation in turn promotes the clearance of circulating triglycerides by inducing apolipoprotein C-II, very low-density lipoproteins receptor (VLDL-R) and the expression of Syndecan-1 together with the repression of apolipoprotein C-III, which increases lipoprotein lipase activity. There is currently minimal clinical data on triglyceride metabolism in patients with bile acid diarrhoea (BAD). Emerging data suggests that a third of patients with BAD have hypertriglyceridemia. Further research is required to establish the risk of hypertriglyceridaemia in patients with BAD and elicit the mechanisms behind this, allowing for targeted treatment. PMID:27570415

Effect of carbohydrate intake on de novo lipogenesis in human adipose tissue

International Nuclear Information System (INIS)

Chascione, C.; Elwyn, D.H.; Davila, M.; Gil, K.M.; Askanazi, J.; Kinney, J.M.

1987-01-01

Rates of synthesis, from [ 14 C]glucose, of fatty acids (de novo lipogenesis) and glycerol (triglyceride synthesis) were measured in biopsies of adipose tissue from nutritionally depleted patients given low- or high-carbohydrate intravenous nutrition. Simultaneously, energy expenditure and whole-body lipogenesis were measured by indirect calorimetry. Rates of whole-body lipogenesis were zero on the low-carbohydrate diet and averaged 1.6 g·kg -1 ·day -1 on the high-carbohydrate diet. In vitro rates of triglyceride synthesis increased 3-fold going from the low to the high intake; rates of fatty acid synthesis increased ∼80-fold. In vitro, lipogenesis accounted for <0.1% of triglyceride synthesis on the low intake and 4% on the high intake. On the high-carbohydrate intake, in vitro rates of triglyceride synthesis accounted for 61% of the rates of unidirectional triglyceride synthesis measured by indirect calorimetry. In vitro rates of lipogenesis accounted for 7% of whole-body lipogenesis. Discrepancies between in vitro rates of fatty acid synthesis from glucose, compared with acetate and citrate, as reported by others, suggest that in depleted patients on hypercaloric high-carbohydrate diets, adipose tissue may account for up to 40% of whole-body lipogenesis

Differential regulation of lipid and protein metabolism in obese vs. lean subjects before and after a 72-h fast

DEFF Research Database (Denmark)

Bak, Ann Mosegaard; Møller, Andreas Buch; Vendelbo, Mikkel Holm

2016-01-01

release in obese subjects under basal and fasting conditions. We therefore studied nine lean and nine obese subjects twice, after 12 and 72 h of fasting, using measurements of mRNA and protein expression and phosphorylation of lipolytic and protein metabolic signaling molecules in fat and muscle together...... with whole body and forearm tracer techniques. Obese subjects displayed increased whole body lipolysis, decreased urea production rates, and decreased forearm muscle protein breakdown per 100 ml of forearm tissue, differences that persisted after 72 h of fasting. Lipolysis per fat mass unit was reduced...... in obese subjects and, correspondingly, adipose tissue hormone-sensitive lipase (HSL) phosphorylation and mRNA and protein levels of the adipose triglyceride lipase (ATGL) coactivator CGI58 were decreased. Fasting resulted in higher HSL phosphorylations and lower protein levels of the ATGL inhibitor G0S2...

Simple anthropometric measures correlate with metabolic risk indicators as strongly as magnetic resonance imaging-measured adipose tissue depots in both HIV-infected and control subjects.

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Scherzer, Rebecca; Shen, Wei; Bacchetti, Peter; Kotler, Donald; Lewis, Cora E; Shlipak, Michael G; Heymsfield, Steven B; Grunfeld, Carl

2008-06-01

Studies in persons without HIV infection have compared percentage body fat (%BF) and waist circumference as markers of risk for the complications of excess adiposity, but only limited study has been conducted in HIV-infected subjects. We compared anthropometric and magnetic resonance imaging (MRI)-based adiposity measures as correlates of metabolic complications of adiposity in HIV-infected and control subjects. The study was a cross-sectional analysis of 666 HIV-positive and 242 control subjects in the Fat Redistribution and Metabolic Change in HIV Infection (FRAM) study assessing body mass index (BMI), waist (WC) and hip (HC) circumferences, waist-to-hip ratio (WHR), %BF, and MRI-measured regional adipose tissue. Study outcomes were 3 metabolic risk variables [homeostatic model assessment (HOMA), triglycerides, and HDL cholesterol]. Analyses were stratified by sex and HIV status and adjusted for demographic, lifestyle, and HIV-related factors. In HIV-infected and control subjects, univariate associations with HOMA, triglycerides, and HDL were strongest for WC, MRI-measured visceral adipose tissue, and WHR; in all cases, differences in correlation between the strongest measures for each outcome were small (r HDL, WC appeared to be the best anthropometric correlate of metabolic complications, whereas, for triglycerides, the best was WHR. Relations of simple anthropometric measures with HOMA, triglycerides, and HDL cholesterol are approximately as strong as MRI-measured whole-body adipose tissue depots in both HIV-infected and control subjects.

Selective deuteration for molecular insights into the digestion of medium chain triglycerides.

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Salentinig, Stefan; Yepuri, Nageshwar Rao; Hawley, Adrian; Boyd, Ben J; Gilbert, Elliot; Darwish, Tamim A

2015-09-01

Medium chain triglycerides (MCTs) are a unique form of dietary fat that have a wide range of health benefits. They are molecules with a glycerol backbone esterified with medium chain (6-12 carbon atoms) fatty acids on the two outer (sn-1 and sn-3) and the middle (sn-2) positions. During lipid digestion in the gastrointestinal tract, pancreatic lipase stereoselectively hydrolyses the ester bonds of these triglycerides on the sn-1 and sn-3 positions resulting in sn-2 monoglyceride and fatty acids as major products. However, the sn-2 monoglycerides are thermodynamically less stable than their sn-1/3 counterparts. Isomerization or fatty acid migration from the sn-2 monoglyceride to sn-1/3 monoglyceride may occur spontaneously and would lead to glycerol and fatty acid as final products. Here, tricaprin (C10) with selectively deuterated fatty acid chains was used for the first time to monitor chain migration and the stereoselectivity of the pancreatic lipase-catalyzed hydrolysis of ester bonds. The intermediate and final digestion products were studied using NMR and mass spectrometry under biologically relevant conditions. The hydrolysis of the sn-2 monocaprin to glycerol and capric acid did not occur within biologically relevant timescales and fatty acid migration occurs only in limited amounts as a result of the presence of undigested diglyceride species over long periods of time in the digestion medium. The slow kinetics for the exchange of the sn-2 fatty acid chain and the stereoselectivity of pancreatic lipase on MCTs is relevant for industrial processes that involve enzymatic interesterification and the production of high-value products such as specific structured triacylglycerols, confectionery fats and nutritional products. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Adiposity distribution influences circulating adiponectin levels

Science.gov (United States)

Guenther, Mitchell; James, Roland; Marks, Jacqueline; Zhao, Shi; Szabo, Aniko; Kidambi, Srividya

2015-01-01

Thirty percent of obese individuals are metabolically healthy and were noted have increased peripheral obesity. Adipose tissue is the primary source of adiponectin, an adipokine with insulin-sensitizing and anti-inflammatory properties. Lower adiponectin levels are observed in individuals with obesity and those at risk for cardiovascular disease. Conversely, higher levels are noted in some obese individuals who are metabolically healthy. Our objective was to determine whether abdominal adiposity distribution, rather than BMI status, influences plasma adiponectin level. Four-hundred and twenty-four subjects (female: 255) of Northern European ancestry were recruited from “Take Off Pounds Sensibly” (TOPS) weight loss club members. Demographics, anthropometrics, and dual X-ray absorptiometry of the whole body and CT scan of the abdomen were performed to obtain total body fat content and to quantify subcutaneous adipose tissue and visceral adipose tissue respectively. Laboratory measurements included fasting plasma glucose, insulin, lipid panel, and adiponectin. Age- and gender-adjusted correlation analyses showed that adiponectin levels were negatively correlated with body mass index, waist circumference, triglycerides, total fat mass, and visceral adipose tissue. A positive correlation was noted with HDL-cholesterol and fat free mass (padipose tissue -to-visceral adipose tissue ratios were also significantly associated with adiponectin (r=0.13, p = 0.001). Further, the best positive predictors for plasma adiponectin were found to be subcutaneous adipose tissue -to-visceral adipose tissue ratios and gender by regression analyses (Padiposity distribution is an important predictor of plasma adiponectin and obese individuals with higher subcutaneous adipose tissue -to-visceral adipose tissue ratios may have higher adiponectin levels. PMID:24811003

Body fat and blood rheology: Evaluation of the association between different adiposity indices and blood viscosity.

Science.gov (United States)

Tripolino, Cesare; Irace, Concetta; Carallo, Claudio; Scavelli, Faustina Barbara; Gnasso, Agostino

2017-01-01

In recent years, new measures of body adiposity have been introduced: lipid accumulation product (LAP), body adiposity index (BAI) and body shape index (ABSI). These indices have been demonstrated to better associate with cardiovascular disease than other measures of adiposity. The aim of the present study was to evaluate if LAP or BAI better associate with blood viscosity than other measures of adiposity (body mass index, BMI; waist circumference, WC; waist-to-hip ratio, W/HR; waist-to-height ratio, W/HtR). 344 subjects were recruited for the present investigation. Exclusion criteria were: diabetes, elevated triglycerides, smoking and drug use. Blood lipids and glucose were measured by routine methods. Blood and plasma viscosity were measured by a cone-plate viscometer. Adiposity measures were computed as previously described. In simple correlation analyses, blood viscosity (BV) correlated with BMI, BAI, and LAP in males and with LAP in females. Correlations between plasma viscosity and adiposity indices were weak and not statistically significant. Other variables significantly related with BV were: gender, HDL- and LDL-Cholesterol, and triglycerides (p index is strongly associated to blood viscosity. This result, along with previous evidence, identifies LAP index as a potential cardiovascular risk marker.

Biodiesel production by using lipase immobilized onto novel silica-based hybrid foams

Energy Technology Data Exchange (ETDEWEB)

Brun, Nicolas [Centre de Recherche Paul Pascal, Pessac (France); Institut des Sciences Moleculaires, Talence (France); Garcia, Annick Babeau; Oestreicher, Victor; Durand, Fabien; Backov, Renal [Centre de Recherche Paul Pascal, Pessac (France); Deleuze, Herve [Institut des Sciences Moleculaires, Talence (France); Laurent, Guillaume; Sanchez, Clement [Laboratoire de Chimie de la Matiere Condensee, Paris (France)

2010-07-01

The covalent immobilization of crude lipases within silica-based macroporous frameworks have been performed by combining sol-gel process, concentrated direct emulsion, lyotropic mesophase and post-synthesis functionalizations. The assynthesized open cell hybrid monoliths exhibit high macroscopic porosity, around 90%, providing interconnected scaffold while reducing the diffusion low kinetic issue. The entrapment of enzymes in such foams deals with a high stability over esterification of fatty acids, hydrolysis of triglycerides (not shown herein) and biodiesel production by transesterification. (orig.)

Low nonfasting triglycerides and reduced all-cause mortality: a mendelian randomization study.

Science.gov (United States)

Thomsen, Mette; Varbo, Anette; Tybjærg-Hansen, Anne; Nordestgaard, Børge G

2014-05-01

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. 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). During a median 24 and 17 years of 100% complete follow-up, 9991 and 4005 individuals died in observational and genetic analyses, respectively. In observational analyses compared to individuals with nonfasting plasma triglycerides of 266-442 mg/dL (3.00-4.99 mmol/L), multivariably adjusted hazard ratios for all-cause mortality were 0.89 (95% CI 0.78-1.02) for 177-265 mg/dL (2.00-2.99 mmol/L), 0.74 (0.65-0.84) for 89-176 mg/dL (1.00-1.99 mmol/L), and 0.59 (0.51-0.68) for individuals with nonfasting triglycerides triglycerides was 0.50 (0.30-0.82), with a corresponding observational hazard ratio of 0.87 (0.85-0.89). Also, the odds ratio for a genetically derived 50% lower concentration in nonfasting triglycerides was 0.43 (0.23-0.80), with a corresponding observational hazard ratio of 0.73 (0.70-0.77). Genetically reduced concentrations of nonfasting plasma triglycerides are associated with reduced all-cause mortality, likely through reduced amounts of cholesterol in remnant lipoproteins.

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

Directory of Open Access Journals (Sweden)

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.

Detection of triglycerides using immobilized enzymes in food and biological samples

Science.gov (United States)

Raichur, Ashish; Lesi, Abiodun; Pedersen, Henrik

1996-04-01

A scheme for the determination of total triglyceride (fat) content in biomedical and food samples is being developed. The primary emphasis is to minimize the reagents used, simplify sample preparation and develop a robust system that would facilitate on-line monitoring. The new detection scheme developed thus far involves extracting triglycerides into an organic solvent (cyclohexane) and performing partial least squares (PLS) analysis on the NIR (1100 - 2500 nm) absorbance spectra of the solution. A training set using 132 spectra of known triglyceride mixtures was complied. Eight PLS calibrations were generated and were used to predict the total fat extracted from commercial samples such as mayonnaise, butter, corn oil and coconut oil. The results typically gave a correlation coefficient (r) of 0.99 or better. Predictions were typically within 90% and better at higher concentrations. Experiments were also performed using an immobilized lipase reactor to hydrolyze the fat extracted into the organic solvent. Performing PLS analysis on the difference spectra of the substrate and product could enhance specificity. This is being verified experimentally. Further work with biomedical samples is to be performed. This scheme may be developed into a feasible detection method for triglycerides in the biomedical and food industries.

Offspring from mothers fed a 'junk food' diet in pregnancy and lactation exhibit exacerbated adiposity that is more pronounced in females.

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Bayol, S A; Simbi, B H; Bertrand, J A; Stickland, N C

2008-07-01

We have shown previously that a maternal junk food diet during pregnancy and lactation plays a role in predisposing offspring to obesity. Here we show that rat offspring born to mothers fed the same junk food diet rich in fat, sugar and salt develop exacerbated adiposity accompanied by raised circulating glucose, insulin, triglyceride and/or cholesterol by the end of adolescence (10 weeks postpartum) compared with offspring also given free access to junk food from weaning but whose mothers were exclusively fed a balanced chow diet in pregnancy and lactation. Results also showed that offspring from mothers fed the junk food diet in pregnancy and lactation, and which were then switched to a balanced chow diet from weaning, exhibited increased perirenal fat pad mass relative to body weight and adipocyte hypertrophy compared with offspring which were never exposed to the junk food diet. This study shows that the increased adiposity was more enhanced in female than male offspring and gene expression analyses showed raised insulin-like growth factor-1 (IGF-1), insulin receptor substrate (IRS)-1, vascular endothelial growth factor (VEGF)-A, peroxisome proliferator-activated receptor-gamma (PPARgamma), leptin, adiponectin, adipsin, lipoprotein lipase (LPL), Glut 1, Glut 3, but not Glut 4 mRNA expression in females fed the junk food diet throughout the study compared with females never given access to junk food. Changes in gene expression were not as marked in male offspring with only IRS-1, VEGF-A, Glut 4 and LPL being up-regulated in those fed the junk food diet throughout the study compared with males never given access to junk food. This study therefore shows that a maternal junk food diet promotes adiposity in offspring and the earlier onset of hyperglycemia, hyperinsulinemia and/or hyperlipidemia. Male and female offspring also display a different metabolic, cellular and molecular response to junk-food-diet-induced adiposity.

ApoE and the role of very low density lipoproteins in adipose tissue inflammation

Science.gov (United States)

Our goal was too identify the role of triglyceride-rich lipoproteins and apoE, a major apolipoprotein in triglyceride-rich lipoproteins, in adipose tissue inflammation with high-fat diet induced obesity. Male apoE-/- and C57BL/6J wild-type mice fed high fat diets for 12 weeks were assessed for metab...

Thermostable, alkaline and detergent-tolerant lipase from a newly isolated thermophilic Bacillus stearothermophilus.

Science.gov (United States)

Ben Bacha, Abir; Moubayed, Nadine M S; Abid, Islam

2015-04-01

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 this study, a novel thermo-alkaline lipase-producing strain identified as Bacillus stearothermophilus was isolated from the soil samples of olive oil mill. Enhanced lipase production was observed at 55 degrees C, pH 11 and after 48 h of incubation. Among the substrates tested, xylose (a carbon source), peptone (a nitrogen source) and olive oil at a concentration of 1% were suitable substrates for enhancing lipase production. MgSO4 and Tween-80 were suitable substrates for maximizing lipase production. The enzyme was purified to homogeneity by a single CM-Sephadex column chromatography and revealed molecular mass of 67 kDa. The enzyme (BL1) was active over a wide range of pH from 9.0 to 13.0, with an optimum at pH 11.0, exhibited maximal activity at 55 degreesC and retained more than 70% of its activity after incubation at 70 degrees C or pH 13 for 0.5 h or 24 h, respectively. The enzyme hydrolyzed both short and long-chain triacylglycerols at comparable rates. BL1 was studied in a preliminary evaluation for use in detergent formulation solutions. This novel lipase showed extreme stability towards non-ionic and anionic surfactants after pre-incubation for 1 h at 40 degrees C, and good stability towards oxidizing agents. Additionally, the enzyme showed excellent stability and compatibility with various commercial detergents, suggesting its potential as an additive in detergent formulations.

Effect of functional sympathetic nervous system impairment of the liver and abdominal visceral adipose tissue on circulating triglyceride-rich lipoproteins.

Directory of Open Access Journals (Sweden)

Michael F La Fountaine

Full Text Available Interruption of sympathetic innervation to the liver and visceral adipose tissue (VAT in animal models has been reported to reduce VAT lipolysis and hepatic secretion of very low density lipoprotein (VLDL and concentrations of triglyceride-rich lipoprotein particles. Whether functional impairment of sympathetic nervous system (SNS innervation to tissues of the abdominal cavity reduce circulating concentrations of triglyceride (TG and VLDL particles (VLDL-P was tested in men with spinal cord injury (SCI.One hundred-three non-ambulatory men with SCI [55 subjects with neurologic injury at or proximal to the 4th thoracic vertebrae (↑T4; 48 subjects with SCI at or distal to the 5th thoracic vertebrae (↓T5] and 53 able-bodied (AB subjects were studied. Fasting blood samples were obtained for determination of TG, VLDL-P concentration by NMR spectroscopy, serum glucose by autoanalyzer, and plasma insulin by radioimmunoassay. VAT volume was determined by dual energy x-ray absorptiometry imaging with calculation by a validated proprietary software package.Significant group main effects for TG and VLDL-P were present; post-hoc tests revealed that serum TG concentrations were significantly higher in ↓T5 group compared to AB and ↑T4 groups [150±9 vs. 101±8 (p<0.01 and 112±8 mg/dl (p<0.05, respectively]. VLDL-P concentration was significantly elevated in ↓T5 group compared to AB and ↑T4 groups [74±4 vs. 58±4 (p<0.05 and 55±4 μmol/l (p<0.05]. VAT volume was significantly higher in both SCI groups than in the AB group, and HOMA-IR was higher and approached significance in the SCI groups compared to the AB group. A linear relationship between triglyceride rich lipoproteins (i.e., TG or Large VLDL-P and VAT volume or HOMA-IR was significant only in the ↓T5 group.Despite a similar VAT volume and insulin resistance in both SCI groups, the ↓T5 group had significantly higher serum TG and VLDL-P values than that observed in the ↑T4 and the AB

Uremic Toxins and Lipases in Haemodialysis: A Process of Repeated Metabolic Starvation

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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.

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. Copyright © 2016 Elsevier B.V. All rights reserved.

High-fat diet-induced adiposity, adipose inflammation, hepatic steatosis and hyperinsulinemia in outbred CD-1 mice.

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Gao, Mingming; Ma, Yongjie; Liu, Dexi

2015-01-01

High-fat diet (HFD) has been applied to a variety of inbred mouse strains to induce obesity and obesity related metabolic complications. In this study, we determined HFD induced development of metabolic disorders on outbred female CD-1 mice in a time dependent manner. Compared to mice on regular chow, HFD-fed CD-1 mice gradually gained more fat mass and consequently exhibited accelerated body weight gain, which was associated with adipocyte hypertrophy and up-regulated expression of adipose inflammatory chemokines and cytokines such as Mcp-1 and Tnf-α. Increased fat accumulation in white adipose tissue subsequently led to ectopic fat deposition in brown adipose tissue, giving rise to whitening of brown adipose tissue without altering plasma level of triglyceride. Ectopic fat deposition was also observed in the liver, which was associated with elevated expression of key genes involved in hepatic lipid sequestration, including Ppar-γ2, Cd36 and Mgat1. Notably, adipose chronic inflammation and ectopic lipid deposition in the liver and brown fat were accompanied by glucose intolerance and insulin resistance, which was correlated with hyperinsulinemia and pancreatic islet hypertrophy. Collectively, these results demonstrate sequentially the events that HFD induces physiological changes leading to metabolic disorders in an outbred mouse model more closely resembling heterogeneity of the human population.

The LPL S447X cSNP is associated with decreased blood pressure and plasma triglycerides, and reduced risk of coronary artery disease

NARCIS (Netherlands)

Clee, S. M.; Loubser, O.; Collins, J.; Kastelein, J. J.; Hayden, M. R.

2001-01-01

Linkage of the lipoprotein lipase (LPL) gene to blood pressure levels has been reported. The LPL S447X single nucleotide polymorphism (cSNP) has been associated with decreased triglycerides (TG), increased high density lipoprotein cholesterol, and a decreased risk of coronary artery disease (CAD),

Heterozygous deficiency of endoglin decreases insulin and hepatic triglyceride levels during high fat diet.

Directory of Open Access Journals (Sweden)

Daniel Beiroa

Full Text Available Endoglin is a transmembrane auxiliary receptor for transforming growth factor-beta (TGF-beta that is predominantly expressed on proliferating endothelial cells. It plays a wide range of physiological roles but its importance on energy balance or insulin sensitivity has been unexplored. Endoglin deficient mice die during midgestation due to cardiovascular defects. Here we report for first time that heterozygous endoglin deficiency in mice decreases high fat diet-induced hepatic triglyceride content and insulin levels. Importantly, these effects are independent of changes in body weight or adiposity. At molecular level, we failed to detect relevant changes in the insulin signalling pathway at basal levels in liver, muscle or adipose tissues that could explain the insulin-dependent effect. However, we found decreased triglyceride content in the liver of endoglin heterozygous mice fed a high fat diet in comparison to their wild type littermates. Overall, our findings indicate that endoglin is a potentially important physiological mediator of insulin levels and hepatic lipid metabolism.

Adipose cell differentiation: evidence for a two-step process in the polyamine-dependent Ob1754 clonal line.

Science.gov (United States)

Amri, E Z; Dani, C; Doglio, A; Etienne, J; Grimaldi, P; Ailhaud, G

1986-01-01

A subclone of preadipocyte Ob17 cells has been isolated (Ob1754 clonal line). Confluent Ob1754 cells treated with an inhibitor of spermidine and spermine synthesis, methylglyoxal bis(guanylhydrazone), were totally dependent upon putrescine addition for the expression of glycerol-3-phosphate dehydrogenase which behaved as a late marker of adipose conversion. Under these conditions, the early expression of lipoprotein lipase during growth arrest remained unchanged. Studies at the mRNA level showed that the expression of unidentified pOb24 and pGH3 mRNAs, which was parallel to that of lipoprotein lipase, is independent of polyamine addition whereas the late emergence of glycerol-3-phosphate dehydrogenase mRNA was putrescine-dependent and co-ordinated with the expression of pAL422 mRNA encoding for a myelin-P2 homologue [Bernlohr, Angus, Lane, Bolanowski & Kelly (1984) Proc. Natl. Acad. Sci. U.S.A. 81, 5468-5472]. The appearance of lipoprotein lipase preceded DNA synthesis and post-confluent mitoses which were both putrescine-dependent and which took place before the appearance of glycerol-3-phosphate dehydrogenase. Thus the adipose conversion of Ob1754 cells involves the expression of at least two separate sets of markers which are differently regulated. Images Fig. 3. Fig. 6. PMID:3800927

Plasma apolipoprotein C-III levels, triglycerides, and coronary artery calcification in type 2 diabetics.

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Qamar, Arman; Khetarpal, Sumeet A; Khera, Amit V; Qasim, Atif; Rader, Daniel J; Reilly, Muredach P

2015-08-01

Triglyceride-rich lipoproteins have emerged as causal risk factors for developing coronary heart disease independent of low-density lipoprotein cholesterol levels. Apolipoprotein C-III (ApoC-III) modulates triglyceride-rich lipoprotein metabolism through inhibition of lipoprotein lipase and hepatic uptake of triglyceride-rich lipoproteins. Mutations causing loss-of-function of ApoC-III lower triglycerides and reduce coronary heart disease risk, suggestive of a causal role for ApoC-III. Little data exist about the relationship of ApoC-III, triglycerides, and atherosclerosis in patients with type 2 diabetes mellitus (T2DM). Here, we examined the relationships between plasma ApoC-III, triglycerides, and coronary artery calcification in patients with T2DM. Plasma ApoC-III levels were measured in a cross-sectional study of 1422 subjects with T2DM but without clinically manifest coronary heart disease. ApoC-III levels were positively associated with total cholesterol (Spearman r=0.36), triglycerides (r=0.59), low-density lipoprotein cholesterol (r=0.16), fasting glucose (r=0.16), and glycosylated hemoglobin (r=0.12; Ptriglycerides (Tobit regression ratio, 1.43; 95% confidence interval, 0.94-2.18; P=0.086) and separately for very low-density lipoprotein cholesterol (Tobit regression ratio, 1.14; 95% confidence interval, 0.75-1.71; P=0.53). In persons with T2DM, increased plasma ApoC-III is associated with higher triglycerides, less favorable cardiometabolic phenotypes, and higher coronary artery calcification, a measure of subclinical atherosclerosis. Therapeutic inhibition of ApoC-III may thus be a novel strategy for reducing plasma triglyceride-rich lipoproteins and cardiovascular risk in T2DM. © 2015 American Heart Association, Inc.

Metabolic Circuit Involving Free Fatty Acids, microRNA 122, and Triglyceride Synthesis in Liver and Muscle Tissues.

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Chai, Chofit; Rivkin, Mila; Berkovits, Liav; Simerzin, Alina; Zorde-Khvalevsky, Elina; Rosenberg, Nofar; Klein, Shiri; Yaish, Dayana; Durst, Ronen; Shpitzen, Shoshana; Udi, Shiran; Tam, Joseph; Heeren, Joerg; Worthmann, Anna; Schramm, Christoph; Kluwe, Johannes; Ravid, Revital; Hornstein, Eran; Giladi, Hilla; Galun, Eithan

2017-11-01

Effective treatments are needed for hepatic steatosis characterized by accumulation of triglycerides in hepatocytes, which leads to hepatocellular carcinoma. MicroRNA 122 (MIR122) is expressed only in the liver, where it regulates lipid metabolism. We investigated the mechanism by which free fatty acids (FFAs) regulate MIR122 expression and the effect of MIR122 on triglyceride synthesis. We analyzed MIR122 promoter activity and validated its target mRNAs by transfection of Luciferase reporter plasmids into Huh7, BNL-1ME, and HEK293 cultured cell lines. We measured levels of microRNAs and mRNAs by quantitative real-time PCR analysis of RNA extracted from plasma, liver, muscle, and adipose tissues of C57BL/6 mice given the FFA-inducer CL316243. MIR122 was inhibited using an inhibitor of MIR122. Metabolic profiles of mice were determined using metabolic chambers and by histologic analyses of liver tissues. We performed RNA sequence analyses to identify metabolic pathways involving MIR122. We validated human Agpat1 and Dgat1 mRNAs, involved in triglyceride synthesis, as targets of MIR122. FFAs increased MIR122 expression in livers of mice by activating the retinoic acid-related orphan receptor alpha, and induced secretion of MIR122 from liver to blood. Circulating MIR122 entered muscle and adipose tissues of mice, reducing mRNA levels of genes involved in triglyceride synthesis. Mice injected with an inhibitor of MIR122 and then given CL316243, accumulated triglycerides in liver and muscle tissues, and had reduced rates of β-oxidation. There was a positive correlation between level of FFAs and level of MIR122 in plasma samples from 6 healthy individuals, collected before and during fasting. In biochemical and histologic studies of plasma, liver, muscle, and adipose tissues from mice, we found that FFAs increase hepatic expression and secretion of MIR122, which regulates energy storage vs expenditure in liver and peripheral tissues. Strategies to reduce

Deficiency of lipoprotein lipase in neurons modifies the regulation of energy balance and leads to obesity

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Wang, H; Astarita, G; Taussig, MD; Bharadwaj, KG; Dipatrizio, NV; Nave, KA; Piomelli, D; Goldberg, IJ; Eckel, RH

2011-01-01

Free fatty acids (FFAs) suppress appetite when injected into the hypothalamus. To examine whether lipoprotein lipase (LPL), a serine hydrolase that releases FFAs from circulating triglyceride (TG)-rich lipoproteins, might contribute to FFA-mediated signaling in the brain, we created neuron-specific LPL-deficient mice. Homozygous mutant (NEXLPL-/-) mice were hyperphagic and became obese by 16 weeks of age. These traits were accompanied by elevations in the hypothalamic orexigenic neuropeptides...

Adipose tissue transcriptome changes during obesity development in female dogs.

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Grant, Ryan W; Vester Boler, Brittany M; Ridge, Tonya K; Graves, Thomas K; Swanson, Kelly S

2011-03-29

During the development of obesity, adipose tissue undergoes major expansion and remodeling, but the biological processes involved in this transition are not well understood. The objective of this study was to analyze global gene expression profiles of adipose tissue in dogs, fed a high-fat diet, during the transition from a lean to obese phenotype. Nine female beagles (4.09 ± 0.64 yr; 8.48 ± 0.35 kg) were randomized to ad libitum feeding or body weight maintenance. Subcutaneous adipose tissue biopsy, blood, and dual x-ray absorptiometry measurements were collected at 0, 4, 8, 12, and 24 wk of feeding. Serum was analyzed for glucose, insulin, fructosamine, triglycerides, free fatty acids, adiponectin, and leptin. Formalin-fixed adipose tissue was used for determination of adipocyte size. Adipose RNA samples were hybridized to Affymetrix Canine 2.0 microarrays. Statistical analysis, using repeated-measures ANOVA, showed ad libitum feeding increased (P obesity development.

Early onset of Chanarin-Dorfman syndrome with severe liver involvement in a patient with a complex rearrangement of ABHD5 promoter

OpenAIRE

Missaglia, Sara; Valadares, Eugenia Ribeiro; Moro, Laura; Faguntes, Eleonora Druve Tavares; quintão Roque, Raquel; Giardina, Bruno; Tavian, Daniela

2014-01-01

Background α/β-hydrolase domain-containing protein 5 (ABHD5) plays an important role in the triacylglycerols (TAG) hydrolysis. Indeed, ABHD5 is the co-activator of adipose triglyceride lipase (ATGL), that catalyses the initial step of TAG hydrolysis. Mutations in ABHD5 gene are associated with the onset of Chanarin-Dorfman syndrome (CDS), a rare autosomal recessive lipid storage disorder, characterized by non-bullous congenital ichthyosiform erythroderma (NCIE), hepatomegaly and liver steatos...

Functional Characterization of Preadipocytes Derived from Human Periaortic Adipose Tissue

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Diana Vargas

2017-01-01

Full Text Available Adipose tissue can affect the metabolic control of the cardiovascular system, and its anatomic location can affect the vascular function differently. In this study, biochemical and phenotypical characteristics of adipose tissue from periaortic fat were evaluated. Periaortic and subcutaneous adipose tissues were obtained from areas surrounding the ascending aorta and sternotomy incision, respectively. Adipose tissues were collected from patients undergoing myocardial revascularization or mitral valve replacement surgery. Morphological studies with hematoxylin/eosin and immunohistochemical assay were performed in situ to quantify adipokine expression. To analyze adipogenic capacity, adipokine expression, and the levels of thermogenic proteins, adipocyte precursor cells were isolated from periaortic and subcutaneous adipose tissues and induced to differentiation. The precursors of adipocytes from the periaortic tissue accumulated less triglycerides than those from the subcutaneous tissue after differentiation and were smaller than those from subcutaneous adipose tissue. The levels of proteins involved in thermogenesis and energy expenditure increased significantly in periaortic adipose tissue. Additionally, the expression levels of adipokines that affect carbohydrate metabolism, such as FGF21, increased significantly in mature adipocytes induced from periaortic adipose tissue. These results demonstrate that precursors of periaortic adipose tissue in humans may affect cardiovascular events and might serve as a target for preventing vascular diseases.

Serum triglycerides, but not cholesterol or leptin, are decreased in suicide attempters with mood disorders.

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da Graça Cantarelli, Maria; Nardin, Patrícia; Buffon, Andréia; Eidt, Murilo Castilhos; Antônio Godoy, Luiz; Fernandes, Brisa S; Gonçalves, Carlos-Alberto

2015-02-01

Many peripheral biomarkers, including low cholesterol and its fractions, have been examined to identify suicidal behavior. Herein, we assessed serum lipid profile and some proteins putatively associated with suicidal behavior in subjects with mood disorder (bipolar disorder or major depressive disorder) with a recent suicide attempt and with no lifetime history of suicide attempts. Fifty subjects had presented an episode of attempted suicide during the last 15 days, and 36 subjects had no history of any suicide attempt. We measured total cholesterol, HDL, LDL and triglycerides as well as serum leptin, brain-derived neurotrophic factor (BDNF), S100B and C-reactive protein (CRP). Individuals that had attempted suicide presented decreased body mass index (BMI) and waist circumference. After adjusting for these confounders, we found that triglycerides were decreased in attempted suicide subjects. We found no differences among total cholesterol, LDL, and HDL or leptin, S100B, CRP and BDNF. This is a cross-sectional study, and we cannot therefore assess whether a decrease in triglycerides caused a mood episode with suicidal ideation that led to a suicide attempt or if the presence of a mood episode originated a loss of appetite and consequent loss of weight, therefore decreasing triglyceride levels. These results do not support the hypothesis that lower levels of cholesterol are associated with suicidal behavior in a mood disorder sample. However, our data support the idea that adiposity is differentiated in these patients (reduced BMI, waist circumference and serum triglycerides), which could lead to an altered communication between the adipose tissue and brain. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

High-fat diet-induced adiposity, adipose inflammation, hepatic steatosis and hyperinsulinemia in outbred CD-1 mice.

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Mingming Gao

Full Text Available High-fat diet (HFD has been applied to a variety of inbred mouse strains to induce obesity and obesity related metabolic complications. In this study, we determined HFD induced development of metabolic disorders on outbred female CD-1 mice in a time dependent manner. Compared to mice on regular chow, HFD-fed CD-1 mice gradually gained more fat mass and consequently exhibited accelerated body weight gain, which was associated with adipocyte hypertrophy and up-regulated expression of adipose inflammatory chemokines and cytokines such as Mcp-1 and Tnf-α. Increased fat accumulation in white adipose tissue subsequently led to ectopic fat deposition in brown adipose tissue, giving rise to whitening of brown adipose tissue without altering plasma level of triglyceride. Ectopic fat deposition was also observed in the liver, which was associated with elevated expression of key genes involved in hepatic lipid sequestration, including Ppar-γ2, Cd36 and Mgat1. Notably, adipose chronic inflammation and ectopic lipid deposition in the liver and brown fat were accompanied by glucose intolerance and insulin resistance, which was correlated with hyperinsulinemia and pancreatic islet hypertrophy. Collectively, these results demonstrate sequentially the events that HFD induces physiological changes leading to metabolic disorders in an outbred mouse model more closely resembling heterogeneity of the human population.

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

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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.

Primeiro relato de uma criança Brasileira portadora da mutação G188E do gene da lipoproteína lipase First report of a Brazilian child carrying the G188E mutation of lipoprotein lipase gene

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Raquel Tiemi Takata

2010-12-01

Full Text Available OBJETIVO: Relatar o caso de uma criança com hipertrigliceridemia grave por mutações do gene da lipoproteína lipase. DESCRIÇÃO DE CASO: Menino de três anos que apresentou, com um mês de idade, soro lipêmico. Seu perfil lipídico indicou hipertrigliceridemia grave, com concentrações de triglicerídeos plasmáticos iguais a 25000mg/dL. Foi detectada a mutação G188E no éxon 5 da lipoproteína lipase em homozigose na criança e em heterozigose nos pais. COMENTÁRIOS: A deficiência da lipoproteína lípase é uma doença de herança autossômica recessiva e esses pacientes evoluem com hipertrigliceridemia grave.OBJECTIVE: To report the case of a child with serious hypertriglyceridemia due to lipase lipoprotein gene mutation. CASE DESCRIPTION: A three-year-old boy presented with lipemic serum at one month of age. His lipid profile revealed serious hypertriglyceridemia with plasma triglycerides levels of 25,000mg/dL. A mutation G188E in éxon 5 of the lipoprotein lipase gene was detected in homozygosis for him and in heterozygosis for his parents. COMMENTS: The deficiency of the lipoprotein lipase is a recessive autossomal disease that causes severe hypertriglyceridemia.

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.

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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...

Atorvastatin decreases apolipoprotein C-III in apolipoprotein B-containing lipoprotein and HDL in type 2 diabetes: a potential mechanism to lower plasma triglycerides

NARCIS (Netherlands)

Dallinga-Thie, Geesje M.; Berk-Planken, Ingrid I. L.; Bootsma, Aart H.; Jansen, Hans

2004-01-01

Apolipoprotein (apo)C-III is a constituent of HDL (HDL apoC-III) and of apoB-containing lipoproteins (LpB:C-III). It slows the clearance of triglyceride-rich lipoproteins (TRLs) by inhibition of the activity of the enzyme lipoprotein lipase (LPL) and by interference with lipoprotein binding to

Evaluation of cellulose-binding domain fused to a lipase for the lipase immobilization.

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Hwang, Sangpill; Ahn, Jungoh; Lee, Sumin; Lee, Tai Gyu; Haam, Seungjoo; Lee, Kangtaek; Ahn, Ik-Sung; Jung, Joon-Ki

2004-04-01

A cellulose-binding domain (CBD) fragment of a cellulase gene of Trichoderma hazianum was fused to a lipase gene of Bacillus stearothermophilus L1 to make a gene cluster for CBD-BSL lipase. The specific activity of CBD-BSL lipase for oil hydrolysis increased by 33% after being immobilized on Avicel (microcrystalline cellulose), whereas those of CBD-BSL lipase and BSL lipase decreased by 16% and 54%, respectively, after being immobilized on silica gel. Although the loss of activity of an enzyme immobilized by adsorption has been reported previously, the loss of activity of the CBD-BSL lipase immobilized on Avicel was less than 3% after 12 h due to the irreversible binding of CBD to Avicel.

Anti-obesity effect of extract from fermented Curcuma longa L. through regulation of adipogenesis and lipolysis pathway in high-fat diet-induced obese rats

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Kim, Ji Hye; Kim, Ok-Kyung; Yoon, Ho-Geun; Park, Jeongjin; You, Yanghee; Kim, Kyungmi; Lee, Yoo-Hyun; Choi, Kyung-Chul; Lee, Jeongmin; Jun, Woojin

2016-01-01

Background Even though Curcuma longa L. possesses various biological activities, it has strong flavor and taste, which decrease consumer palatability and limit industrial applications in food. Objective The present study investigates the effects of C. longa L. fermented with Aspergillus oryzae supplementation in 60% high-fat diet-induced obese rats measured by the activation of adipogenesis and lipolysis. Design Rats were divided into four groups (n=6 per group) after 1 week of acclimatization: a normal diet group comprised rats fed the AIN76A rodent diet; a high-fat diet-induced obese group with rats fed a 60% high-fat diet; a Garcinia cambogia treated group (positive control) with rats fed a 60% high-fat diet with G. cambogia 500 g/kg body weight (b.w.)/day; and an fermented C. longa L. 50% ethanolic extract treated group (FCE50) with rats fed a 60% high-fat diet with FCE50 500 g/kg b.w./day. Each group received the appropriate vehicle or sample daily by gastric intubation for 12 weeks. Results We found that FCE50 administration suppressed b.w. gain and reduced white adipose tissue weight, serum triglyceride (TG), and cholesterol in high-fat diet-induced obese rats. These results can be associated with the suppression of adipocyte differentiation and lipogenesis with a decrease in the mRNA expressions of fatty acid synthase, acetyl-CoA carboxylase, adipocyte protein 2, and lipoprotein lipase induced by FCE50 administration. In addition, FCE50 increased lipolysis and β-oxidation by up-regulating the expression of lipases such as adipose triglyceride lipase, hormone-sensitive lipase, adiponectin, and AMP-activated protein kinase. Conclusions These results suggest that FCE50 can be a candidate for the prevention of obesity via suppressing adipogenesis and promoting lipolysis. PMID:26822962

Classification of different degrees of adiposity in sedentary rats

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Leopoldo, A.S.; Lima-Leopoldo, A.P. [Departamento de Desportos, Centro de Educação Física e Esportes, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Nascimento, A.F.; Luvizotto, R.A.M.; Sugizaki, M.M. [Instituto de Ciências da Saúde, Universidade Federal do Mato Grosso, Sinop, MT (Brazil); Campos, D.H.S.; Silva, D.C.T. da [Departamento de Clínica Médica, Faculdade de Medicina, Universidade Estadual Paulista, Botucatu, SP (Brazil); Padovani, C.R. [Departamento de Bioestatística, Instituto de Biociências, Universidade Estadual Paulista, Botucatu, SP (Brazil); Cicogna, A.C. [Departamento de Clínica Médica, Faculdade de Medicina, Universidade Estadual Paulista, Botucatu, SP (Brazil)

2016-02-23

In experimental studies, several parameters, such as body weight, body mass index, adiposity index, and dual-energy X-ray absorptiometry, have commonly been used to demonstrate increased adiposity and investigate the mechanisms underlying obesity and sedentary lifestyles. However, these investigations have not classified the degree of adiposity nor defined adiposity categories for rats, such as normal, overweight, and obese. The aim of the study was to characterize the degree of adiposity in rats fed a high-fat diet using cluster analysis and to create adiposity intervals in an experimental model of obesity. Thirty-day-old male Wistar rats were fed a normal (n=41) or a high-fat (n=43) diet for 15 weeks. Obesity was defined based on the adiposity index; and the degree of adiposity was evaluated using cluster analysis. Cluster analysis allowed the rats to be classified into two groups (overweight and obese). The obese group displayed significantly higher total body fat and a higher adiposity index compared with those of the overweight group. No differences in systolic blood pressure or nonesterified fatty acid, glucose, total cholesterol, or triglyceride levels were observed between the obese and overweight groups. The adiposity index of the obese group was positively correlated with final body weight, total body fat, and leptin levels. Despite the classification of sedentary rats into overweight and obese groups, it was not possible to identify differences in the comorbidities between the two groups.

Classification of different degrees of adiposity in sedentary rats

International Nuclear Information System (INIS)

Leopoldo, A.S.; Lima-Leopoldo, A.P.; Nascimento, A.F.; Luvizotto, R.A.M.; Sugizaki, M.M.; Campos, D.H.S.; Silva, D.C.T. da; Padovani, C.R.; Cicogna, A.C.

2016-01-01

In experimental studies, several parameters, such as body weight, body mass index, adiposity index, and dual-energy X-ray absorptiometry, have commonly been used to demonstrate increased adiposity and investigate the mechanisms underlying obesity and sedentary lifestyles. However, these investigations have not classified the degree of adiposity nor defined adiposity categories for rats, such as normal, overweight, and obese. The aim of the study was to characterize the degree of adiposity in rats fed a high-fat diet using cluster analysis and to create adiposity intervals in an experimental model of obesity. Thirty-day-old male Wistar rats were fed a normal (n=41) or a high-fat (n=43) diet for 15 weeks. Obesity was defined based on the adiposity index; and the degree of adiposity was evaluated using cluster analysis. Cluster analysis allowed the rats to be classified into two groups (overweight and obese). The obese group displayed significantly higher total body fat and a higher adiposity index compared with those of the overweight group. No differences in systolic blood pressure or nonesterified fatty acid, glucose, total cholesterol, or triglyceride levels were observed between the obese and overweight groups. The adiposity index of the obese group was positively correlated with final body weight, total body fat, and leptin levels. Despite the classification of sedentary rats into overweight and obese groups, it was not possible to identify differences in the comorbidities between the two groups

Skin Barrier Development Depends on CGI-58 Protein Expression during Late-Stage Keratinocyte Differentiation

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Grond, Susanne; Radner, Franz P.W.; Eichmann, Thomas O.; Kolb, Dagmar; Grabner, Gernot F.; Wolinski, Heimo; Gruber, Robert; Hofer, Peter; Heier, Christoph; Schauer, Silvia; Rülicke, Thomas; Hoefler, Gerald; Schmuth, Matthias; Elias, Peter M.; Lass, Achim; Zechner, Rudolf; Haemmerle, Guenter

2017-01-01

Adipose triglyceride lipase (ATGL) and its coactivator comparative gene identification-58 (CGI-58) are limiting in cellular triglyceride catabolism. Although ATGL deficiency is compatible with normal skin development, mice globally lacking CGI-58 die postnatally and exhibit a severe epidermal permeability barrier defect, which may originate from epidermal and/or peripheral changes in lipid and energy metabolism. Here, we show that epidermis-specific disruption of CGI-58 is sufficient to provoke a defect in the formation of a functional corneocyte lipid envelope linked to impaired ω-O-acylceramide synthesis. As a result, epidermis-specific CGI-58-deficient mice show severe skin dysfunction, arguing for a tissue autonomous cause of disease development. Defective skin permeability barrier formation in global CGI-58-deficient mice could be reversed via transgenic restoration of CGI-58 expression in differentiated but not basal keratinocytes suggesting that CGI-58 is essential for lipid metabolism in suprabasal epidermal layers. The compatibility of ATGL deficiency with normal epidermal function indicated that CGI-58 may stimulate an epidermal triglyceride lipase beyond ATGL required for the adequate provision of fatty acids as a substrate for ω-O-acylceramide synthesis. Pharmacological inhibition of ATGL enzyme activity similarly reduced triglyceride-hydrolytic activities in wild-type and CGI-58 overexpressing epidermis implicating that CGI-58 participates in ω-O-acylceramide biogenesis independent of its role as a coactivator of epidermal triglyceride catabolism. PMID:27725204

Glucose intolerance and the amount of visceral adipose tissue contribute to an increase in circulating triglyceride concentrations in Caucasian obese females.

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Berings, Margot; Wehlou, Charline; Verrijken, An; Deschepper, Ellen; Mertens, Ilse; Kaufman, Jean-Marc; Van Gaal, Luc F; Ouwens, D Margriet; Ruige, Johannes B

2012-01-01

Lipotoxicity is a risk factor for developing obesity-related metabolic complications, including non-alcoholic fatty liver disease, type 2 diabetes (DM2), cardiovascular disease and stroke. Yet, the mechanisms underlying the development of lipotoxicity itself remain poorly understood. Here, we investigated whether glucose intolerance aggravates lipotoxicity by evaluating the association between triglyceride (TG) concentrations and glucose tolerance status in a cross-sectional study on obese Caucasian women at risk for DM2. 913 obese females unknown to have diabetes were recruited (mean age: 41.2 ± SD 12.3; median BMI: 36.2, IQR 32.9-40.2). Visceral (VAT) and subcutaneous abdominal adipose tissue volumes were quantified with computed tomography. Glucose, insulin, and triglyceride concentrations were determined in fasting state and following a 75 gram oral glucose tolerance test. Based on fasting and 2 h post-load glucose levels, 27% of the women had impaired glucose tolerance (IGT), and 8% had newly diagnosed DM2. Fasting TG concentrations were similar between the IGT- and DM2-groups, and increased as compared to women with normal glucose tolerance (NGT). Even when adjusting for age, hip circumference and VAT, fasting TG concentrations remained elevated as compared to NGT. Mixed modelling analysis of post-load responses showed that TG concentrations declined more slowly in the DM2-group as compared to IGT and NGT. However, when adjusting for VAT the difference in decline between the glucose tolerance groups disappeared. Glucose intolerance associates with elevated fasting TG concentrations in obese Caucasian women. We propose that glucose intolerance and increased VAT reduce lipid disposal mechanisms and may accelerate lipotoxicity.

Glucose intolerance and the amount of visceral adipose tissue contribute to an increase in circulating triglyceride concentrations in Caucasian obese females.

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Margot Berings

Full Text Available CONTEXT: Lipotoxicity is a risk factor for developing obesity-related metabolic complications, including non-alcoholic fatty liver disease, type 2 diabetes (DM2, cardiovascular disease and stroke. Yet, the mechanisms underlying the development of lipotoxicity itself remain poorly understood. Here, we investigated whether glucose intolerance aggravates lipotoxicity by evaluating the association between triglyceride (TG concentrations and glucose tolerance status in a cross-sectional study on obese Caucasian women at risk for DM2. METHODS: 913 obese females unknown to have diabetes were recruited (mean age: 41.2 ± SD 12.3; median BMI: 36.2, IQR 32.9-40.2. Visceral (VAT and subcutaneous abdominal adipose tissue volumes were quantified with computed tomography. Glucose, insulin, and triglyceride concentrations were determined in fasting state and following a 75 gram oral glucose tolerance test. RESULTS: Based on fasting and 2 h post-load glucose levels, 27% of the women had impaired glucose tolerance (IGT, and 8% had newly diagnosed DM2. Fasting TG concentrations were similar between the IGT- and DM2-groups, and increased as compared to women with normal glucose tolerance (NGT. Even when adjusting for age, hip circumference and VAT, fasting TG concentrations remained elevated as compared to NGT. Mixed modelling analysis of post-load responses showed that TG concentrations declined more slowly in the DM2-group as compared to IGT and NGT. However, when adjusting for VAT the difference in decline between the glucose tolerance groups disappeared. CONCLUSIONS: Glucose intolerance associates with elevated fasting TG concentrations in obese Caucasian women. We propose that glucose intolerance and increased VAT reduce lipid disposal mechanisms and may accelerate lipotoxicity.

Bacterial lipases

NARCIS (Netherlands)

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

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,

Inhibition of lipolysis in the novel transgenic quail model overexpressing G0/G1 switch gene 2 in the adipose tissue during feed restriction.

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Sangsu Shin

Full Text Available In addition to the issue of obesity in humans, the production of low-fat meat from domestic animals is important in the agricultural industry to satisfy consumer demand. Understanding the regulation of lipolysis in adipose tissue could advance our knowledge to potentially solve both issues. Although the G0/G1 switch gene 2 (G0S2 was recently identified as an inhibitor of adipose triglyceride lipase (ATGL in vitro, its role in vivo has not been fully clarified. This study was conducted to investigate the role of G0S2 gene in vivo by using two independent transgenic quail lines during different energy conditions. Unexpectedly, G0S2 overexpression had a negligible effect on plasma NEFA concentration, fat cell size and fat pad weight under ad libitum feeding condition when adipose lipolytic activity is minimal. A two-week feed restriction in non-transgenic quail expectedly caused increased plasma NEFA concentration and dramatically reduced fat cell size and fat pad weight. Contrary, G0S2 overexpression under a feed restriction resulted in a significantly less elevation of plasma NEFA concentration and smaller reductions in fat pad weights and fat cell size compared to non-transgenic quail, demonstrating inhibition of lipolysis and resistance to loss of fat by G0S2. Excessive G0S2 inhibits lipolysis in vivo during active lipolytic conditions, such as food restriction and fasting, suggesting G0S2 as a potential target for treatment of obesity. In addition, transgenic quail are novel models for studying lipid metabolism and mechanisms of obesity.

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

Simple anthropometric measures correlate with metabolic risk indicators as strongly as magnetic resonance imaging–measured adipose tissue depots in both HIV-infected and control subjects2

Science.gov (United States)

Scherzer, Rebecca; Shen, Wei; Bacchetti, Peter; Kotler, Donald; Lewis, Cora E; Shlipak, Michael G; Heymsfield, Steven B

2008-01-01

Background Studies in persons without HIV infection have compared percentage body fat (%BF) and waist circumference as markers of risk for the complications of excess adiposity, but only limited study has been conducted in HIV-infected subjects. Objective We compared anthropometric and magnetic resonance imaging (MRI)–based adiposity measures as correlates of metabolic complications of adiposity in HIV-infected and control subjects. Design The study was a cross-sectional analysis of 666 HIV-positive and 242 control subjects in the Fat Redistribution and Metabolic Change in HIV Infection (FRAM) study assessing body mass index (BMI), waist (WC) and hip (HC) circumferences, waist-to-hip ratio (WHR), %BF, and MRI-measured regional adipose tissue. Study outcomes were 3 metabolic risk variables [homeostatic model assessment (HOMA), triglycerides, and HDL cholesterol]. Analyses were stratified by sex and HIV status and adjusted for demographic, lifestyle, and HIV-related factors. Results In HIV-infected and control subjects, univariate associations with HOMA, triglycerides, and HDL were strongest for WC, MRI-measured visceral adipose tissue, and WHR; in all cases, differences in correlation between the strongest measures for each outcome were small (r ≤ 0.07). Multivariate adjustment found no significant difference for optimally fitting models between the use of anthropometric and MRI measures, and the magnitudes of differences were small (adjusted R2 ≤ 0.06). For HOMA and HDL, WC appeared to be the best anthropometric correlate of metabolic complications, whereas, for triglycerides, the best was WHR. Conclusion Relations of simple anthropometric measures with HOMA, triglycerides, and HDL cholesterol are approximately as strong as MRI-measured whole-body adipose tissue depots in both HIV-infected and control subjects. PMID:18541572

Theoretical model of ruminant adipose tissue metabolism in relation to the whole animal.

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Baldwin, R L; Yang, Y T; Crist, K; Grichting, G

1976-09-01

Based on theoretical considerations and experimental data, estimates of contributions of adipose tissue to energy expenditures in a lactating cow and a growing steer were developed. The estimates indicate that adipose energy expenditures range between 5 and 10% of total animal heat production dependent on productive function and diet. These energy expenditures can be partitioned among maintenance (3%), lipogenesis (1-5%) and lipolysis and triglyceride resynthesis (less thatn 1.0%). Specific sites at which acute and chronic effectors can act to produce changes in adipose function, and changes in adipose function produced by diet and during pregnancy, lactation and aging were discussed with emphasis being placed on the need for additional, definitive studies of specific interactions among pregnancy, diet, age, lactation and growth in producing ruminants.

The regulation of HSL and LPL expression by DHT and flutamide in human subcutaneous adipose tissue.

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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 DHT10(-9) m (2.22 +/- 0.48*; p 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.

Generation of induced Pluripotent Stem Cells as disease modelling of NLSDM

OpenAIRE

Tavian, D.; Missaglia, S.; Castagnetta, M.; Degiorgio, D.; Pennisi, E.M.; Coleman, R.A.; Dell'Era, P.; Mora, C.; Angelini, C.; Coviello, D.A.

2017-01-01

Neutral Lipid Storage Disease with Myopathy (NLSDM) is a rare defect of triacylglycerol metabolism, characterized by the abnormal storage of neutral lipid in organelles known as lipid droplets (LDs). The main clinical features are progressive myopathy and cardiomyopathy. The onset of NLSDM is caused by autosomal recessive mutations in the PNPLA2 gene, which encodes adipose triglyceride lipase (ATGL). Despite its name, this enzyme is present in a wide variety of cell types and catalyzes the fi...

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)

Makoveichuk, Elena; Sukonina, Valentina; Kroupa, Olessia; Thulin, Petra; Ehrenborg, Ewa; Olivecrona, Thomas; Olivecrona, Gunilla

2012-01-01

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.

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)

Salem, E.S.; Tawfik, M.S.; Youssef, S.S.; Serry, Z.M.; Aboel magd, H.F.

2013-01-01

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

Differential patterns of serum concentration and adipose tissue expression of chemerin in obesity: adipose depot specificity and gender dimorphism.

Science.gov (United States)

Alfadda, Assim A; Sallam, Reem M; Chishti, Muhammad Azhar; Moustafa, Amr S; Fatma, Sumbul; Alomaim, Waleed S; Al-Naami, Mohammed Y; Bassas, Abdulelah F; Chrousos, George P; Jo, Hyunsun

2012-06-01

Chemerin, a recognized chemoattractant, is expressed in adipose tissue and plays a role in adipocytes differentiation and metabolism. Gender- and adipose tissue-specific differences in human chemerin expression have not been well characterized. Therefore, these differences were assessed in the present study. The body mass index (BMI) and the circulating levels of chemerin and other inflammatory, adiposity and insulin resistance markers were assessed in female and male adults of varying degree of obesity. Chemerin mRNA expression was also measured in paired subcutaneous and visceral adipose tissue samples obtained from a subset of the study subjects. Serum chemerin concentrations correlated positively with BMI and serum leptin levels and negatively with high density lipoprotein (HDL)-cholesterol levels. No correlation was found between serum chemerin concentrations and fasting glucose, total cholesterol, low density lipoprotein (LDL)-cholesterol, triglycerides, insulin, C-reactive protein or adiponectin. Similarly, no relation was observed with the homeostasis model assessment for insulin resistance (HOMA-IR) values. Gender- and adipose tissue-specific differences were observed in chemerin mRNA expression levels, with expression significantly higher in women than men and in subcutaneous than visceral adipose tissue. Interestingly, we found a significant negative correlation between circulating chemerin levels and chemerin mRNA expression in subcutaneous fat. Among the subjects studied, circulating chemerin levels were associated with obesity markers but not with markers of insulin resistance. At the tissue level, fat depot-specific differential regulation of chemerin mRNA expression might contribute to the distinctive roles of subcutaneous vs. visceral adipose tissue in human obesity.

Insulin Plays a Permissive Role for the Vasoactive Effect of GIP Regulating Adipose Tissue Metabolism in Humans

DEFF Research Database (Denmark)

Asmar, Meena; Simonsen, Lene; Asmar, Ali

2016-01-01

CONTEXT AND OBJECTIVE: Glucose-dependent insulinotropic polypeptide (GIP) in combination with hyperinsulinemia increases blood flow and triglyceride (TAG) clearance in subcutaneous (sc) abdominal adipose tissue in lean humans. The present experiments were performed to further investigate the role...... of insulin for the vasoactive effect of GIP in adipose tissue metabolism and whether the vasodilatory effect of GIP is dependent on C-peptide. METHODS: Six lean healthy subjects were studied. The sc abdominal adipose tissue metabolism was assessed by Fick's principle during GIP infusion (1.5 pmol...

A Diurnal Rhythm in Brown Adipose Tissue Causes Rapid Clearance and Combustion of Plasma Lipids at Wakening

DEFF Research Database (Denmark)

van den Berg, Rosa; Kooijman, Sander; Noordam, Raymond

2018-01-01

-amplitude rhythm in fatty acid uptake by BAT that synchronized with the light/dark cycle. Highest uptake was found at the onset of the active period, which coincided with high lipoprotein lipase expression and low angiopoietin-like 4 expression by BAT. Diurnal rhythmicity in BAT activity determined the rate...... the therapeutic potential of promoting BAT activity. van den Berg et al. show a strong circadian rhythm in fatty acid uptake by brown adipose tissue that peaks at wakening regardless of the light exposure period. Consequently, postprandial lipid handling by brown adipose tissue is highest at wakening, resulting...

Nutrition, insulin resistance and dysfunctional adipose tissue determine the different components of metabolic syndrome

Science.gov (United States)

Paniagua, Juan Antonio

2016-01-01

Obesity is an excessive accumulation of body fat that may be harmful to health. Today, obesity is a major public health problem, affecting in greater or lesser proportion all demographic groups. Obesity is estimated by body mass index (BMI) in a clinical setting, but BMI reports neither body composition nor the location of excess body fat. Deaths from cardiovascular diseases, cancer and diabetes accounted for approximately 65% of all deaths, and adiposity and mainly abdominal adiposity are associated with all these disorders. Adipose tissue could expand to inflexibility levels. Then, adiposity is associated with a state of low-grade chronic inflammation, with increased tumor necrosis factor-α and interleukin-6 release, which interfere with adipose cell differentiation, and the action pattern of adiponectin and leptin until the adipose tissue begins to be dysfunctional. In this state the subject presents insulin resistance and hyperinsulinemia, probably the first step of a dysfunctional metabolic system. Subsequent to central obesity, insulin resistance, hyperglycemia, hypertriglyceridemia, hypoalphalipoproteinemia, hypertension and fatty liver are grouped in the so-called metabolic syndrome (MetS). In subjects with MetS an energy balance is critical to maintain a healthy body weight, mainly limiting the intake of high energy density foods (fat). However, high-carbohydrate rich (CHO) diets increase postprandial peaks of insulin and glucose. Triglyceride-rich lipoproteins are also increased, which interferes with reverse cholesterol transport lowering high-density lipoprotein cholesterol. In addition, CHO-rich diets could move fat from peripheral to central deposits and reduce adiponectin activity in peripheral adipose tissue. All these are improved with monounsaturated fatty acid-rich diets. Lastly, increased portions of ω-3 and ω-6 fatty acids also decrease triglyceride levels, and complement the healthy diet that is recommended in patients with MetS. PMID

Nutrition, insulin resistance and dysfunctional adipose tissue determine the different components of metabolic syndrome

Institute of Scientific and Technical Information of China (English)

Juan; Antonio; Paniagua[1,2

2016-01-01

Obesity is an excessive accumulation of body fat that may be harmful to health. Today, obesity is a major public health problem, affecting in greater or lesser proportion all demographic groups. Obesity is estimated by body mass index (BMI) in a clinical setting, but BMI reports neither body composition nor the location of excess body fat.Deaths from cardiovascular diseases, cancer and diabetes accounted for approximately 65% of all deaths, and adiposity and mainly abdominal adiposity are associated with all these disorders. Adipose tissue could expand to inflexibility levels. Then, adiposity is associated with a state of low-grade chronic inflammation, with increased tumor necrosis factor-α and interleukin-6 release, which interfere with adipose cell differentiation, and the action pattern of adiponectin and leptin until the adipose tissue begins to be dysfunctional. In this state the subject presents insulin resistance and hyperinsulinemia, probably the first step of a dysfunctional metabolic system. Subsequent to central obesity, insulin resistance, hyperglycemia,hypertriglyceridemia, hypoalphalipoproteinemia, hypertension and fatty liver are grouped in the so-called metabolic syndrome (MetS). In subjects with MetS an energy balance is critical to maintain a healthy body weight, mainly limiting the intake of high energy density foods (fat). However, high-carbohydrate rich (CHO) diets increase postprandial peaks of insulin and glucose.Triglyceride-rich lipoproteins are also increased, which interferes with reverse cholesterol transport lowering highdensity lipoprotein cholesterol. In addition, CHO-rich diets could move fat from peripheral to central deposits and reduce adiponectin activity in peripheral adipose tissue. All these are improved with monounsaturated fatty acid-rich diets. Lastly, increased portions of ω-3 and ω-6 fatty acids also decrease triglyceride levels, and complement the healthy diet that is recommended in patients with MetS.

Ursodeoxycholic acid decreases age-related adiposity and inflammation in mice

Science.gov (United States)

Oh, Ah-Reum; Bae, Jin-Sik; Lee, Junghoon; Shin, Eunji; Oh, Byung-Chul; Park, Sang-Chul; Cha, Ji-Young

2016-01-01

Ursodeoxycholic acid (UDCA), a natural, hydrophilic nontoxic bile acid, is clinically effective for treating cholestatic and chronic liver diseases. We investigated the chronic effects of UDCA on age-related lipid homeostasis and underlying molecular mechanisms. Twenty-week-old C57BL/6 male and female mice were fed a diet with or without 0.3% UDCA supplementation for 25 weeks. UDCA significantly reduced weight gain, adiposity, hepatic triglyceride, and hepatic cholesterol without incidental hepatic injury. UDCA-mediated hepatic triglyceride reduction was associated with downregulated hepatic expression of peroxisome proliferator-activated receptor-γ, and of other genes involved in lipogenesis (Chrebp, Acaca, Fasn, Scd1, and Me1) and fatty acid uptake (Ldlr, Cd36). The inflammatory cytokines Tnfa, Ccl2, and Il6 were significantly decreased in liver and/or white adipose tissues of UDCA-fed mice. These data suggest that UDCA exerts beneficial effects on age-related metabolic disorders by lowering the hepatic lipid accumulation, while concurrently reducing hepatocyte and adipocyte susceptibility to inflammatory stimuli. [BMB Reports 2016; 49(2): 105-110] PMID:26350747

Offspring from mothers fed a ‘junk food’ diet in pregnancy and lactation exhibit exacerbated adiposity that is more pronounced in females

Science.gov (United States)

Bayol, S A; Simbi, B H; Bertrand, J A; Stickland, N C

2008-01-01

We have shown previously that a maternal junk food diet during pregnancy and lactation plays a role in predisposing offspring to obesity. Here we show that rat offspring born to mothers fed the same junk food diet rich in fat, sugar and salt develop exacerbated adiposity accompanied by raised circulating glucose, insulin, triglyceride and/or cholesterol by the end of adolescence (10 weeks postpartum) compared with offspring also given free access to junk food from weaning but whose mothers were exclusively fed a balanced chow diet in pregnancy and lactation. Results also showed that offspring from mothers fed the junk food diet in pregnancy and lactation, and which were then switched to a balanced chow diet from weaning, exhibited increased perirenal fat pad mass relative to body weight and adipocyte hypertrophy compared with offspring which were never exposed to the junk food diet. This study shows that the increased adiposity was more enhanced in female than male offspring and gene expression analyses showed raised insulin-like growth factor-1 (IGF-1), insulin receptor substrate (IRS)-1, vascular endothelial growth factor (VEGF)-A, peroxisome proliferator-activated receptor-γ (PPARγ), leptin, adiponectin, adipsin, lipoprotein lipase (LPL), Glut 1, Glut 3, but not Glut 4 mRNA expression in females fed the junk food diet throughout the study compared with females never given access to junk food. Changes in gene expression were not as marked in male offspring with only IRS-1, VEGF-A, Glut 4 and LPL being up-regulated in those fed the junk food diet throughout the study compared with males never given access to junk food. This study therefore shows that a maternal junk food diet promotes adiposity in offspring and the earlier onset of hyperglycemia, hyperinsulinemia and/or hyperlipidemia. Male and female offspring also display a different metabolic, cellular and molecular response to junk-food-diet-induced adiposity. PMID:18467362

Reduced kidney lipoprotein lipase and renal tubule triglyceride accumulation in cisplatin-mediated acute kidney injury

NARCIS (Netherlands)

Li, Shenyang; Nagothu, K.; Ranganathan, G.; Ali, S.M.; Shank, B.; Gokden, N.; Ayyadevara, S.; Megysi, J.; Olivecrona, G.; Chugh, S.S.; Kersten, A.H.; Portilla, D.

2012-01-01

Peroxisome proliferator-activated receptor-a (PPARa) activation attenuates cisplatin (CP)-mediated acute kidney injury by increasing fatty acid oxidation, but mechanisms leading to reduced renal triglyceride (TG) accumulation could also contribute. Here, we investigated the effects of PPARa and CP

Late onset of neutral lipid storage disease due to novel PNPLA2 mutations causing total loss of lipase activity in a patient with myopathy and slight cardiac involvement.

Science.gov (United States)

Missaglia, Sara; Maggi, Lorenzo; Mora, Marina; Gibertini, Sara; Blasevich, Flavia; Agostoni, Piergiuseppe; Moro, Laura; Cassandrini, Denise; Santorelli, Filippo Maria; Gerevini, Simonetta; Tavian, Daniela

2017-05-01

Neutral lipid storage disease with myopathy (NLSDM) presents with skeletal muscle myopathy and severe dilated cardiomyopathy in nearly 40% of cases. NLSDM is caused by mutations in the PNPLA2 gene, which encodes the adipose triglyceride lipase (ATGL). Here we report clinical and genetic findings of a patient carrying two novel PNPLA2 mutations (c.696+4A>G and c.553_565delGTCCCCCTTCTCG). She presented at age 39 with right upper limb abduction weakness slowly progressing over the years with asymmetric involvement of proximal upper and lower limb muscles. Cardiological evaluation through ECG and heart echo scan was normal until the age 53, when mild left ventricular diastolic dysfunction was detected. Molecular analysis revealed that only one type of PNPLA2 transcript, with exon 5 skipping, was expressed in patient cells. Such aberrant mRNA causes the production of a shorter ATGL protein, lacking part of the catalytic domain. This is an intriguing case, displaying severe PNPLA2 mutations with clinical presentation characterized by slight cardiac impairment and full expression of severe asymmetric myopathy. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

PPARα L162V underlies variation in serum triglycerides and subcutaneous fat volume in young males

Directory of Open Access Journals (Sweden)

Clarkson Priscilla M

2007-08-01

Full Text Available Abstract Background Of the five sub-phenotypes defining metabolic syndrome, all are known to have strong genetic components (typically 50–80% of population variation. Studies defining genetic predispositions have typically focused on older populations with metabolic syndrome and/or type 2 diabetes. We hypothesized that the study of younger populations would mitigate many confounding variables, and allow us to better define genetic predisposition loci for metabolic syndrome. Methods We studied 610 young adult volunteers (average age 24 yrs for metabolic syndrome markers, and volumetric MRI of upper arm muscle, bone, and fat pre- and post-unilateral resistance training. Results We found the PPARα L162V polymorphism to be a strong determinant of serum triglyceride levels in young White males, where carriers of the V allele showed 78% increase in triglycerides relative to L homozygotes (LL = 116 ± 11 mg/dL, LV = 208 ± 30 mg/dL; p = 0.004. Men with the V allele showed lower HDL (LL = 42 ± 1 mg/dL, LV = 34 ± 2 mg/dL; p = 0.001, but women did not. Subcutaneous fat volume was higher in males carrying the V allele, however, exercise training increased fat volume of the untrained arm in V carriers, while LL genotypes significantly decreased in fat volume (LL = -1,707 ± 21 mm3, LV = 17,617 ± 58 mm3 ; p = 0.002, indicating a systemic effect of the V allele on adiposity after unilateral training. Our study suggests that the primary effect of PPARα L162V is on serum triglycerides, with downstream effects on adiposity and response to training. Conclusion Our results on association of PPARα and triglycerides in males showed a much larger effect of the V allele than previously reported in older and less healthy populations. Specifically, we showed the V allele to increase triglycerides by 78% (p = 0.004, and this single polymorphism accounted for 3.8% of all variation in serum triglycerides in males (p = 0.0037.

Triglycerides in the Human Kidney Cortex: Relationship with Body Size

Science.gov (United States)

Bobulescu, Ion Alexandru; Lotan, Yair; Zhang, Jianning; Rosenthal, Tara R.; Rogers, John T.; Adams-Huet, Beverley; Sakhaee, Khashayar; Moe, Orson W.

2014-01-01

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. PMID:25170827

A Novel Apolipoprotein C-II Mimetic Peptide That Activates Lipoprotein Lipase and Decreases Serum Triglycerides in Apolipoprotein E–Knockout Mice

Science.gov (United States)

Sakurai, Toshihiro; Sakurai-Ikuta, Akiko; Sviridov, Denis; Freeman, Lita; Ahsan, Lusana; Remaley, Alan T.

2015-01-01

Apolipoprotein A-I (apoA-I) mimetic peptides are currently being developed as possible new agents for the treatment of cardiovascular disease based on their ability to promote cholesterol efflux and their other beneficial antiatherogenic properties. Many of these peptides, however, have been reported to cause transient hypertriglyceridemia due to inhibition of lipolysis by lipoprotein lipase (LPL). We describe a novel bihelical amphipathic peptide (C-II-a) that contains an amphipathic helix (18A) for binding to lipoproteins and stimulating cholesterol efflux as well as a motif based on the last helix of apolipoprotein C-II (apoC-II) that activates lipolysis by LPL. The C-II-a peptide promoted cholesterol efflux from ATP-binding cassette transporter ABCA1-transfected BHK cells similar to apoA-I mimetic peptides. Furthermore, it was shown in vitro to be comparable to the full-length apoC-II protein in activating lipolysis by LPL. When added to serum from a patient with apoC-II deficiency, it restored normal levels of LPL-induced lipolysis and also enhanced lipolysis in serum from patients with type IV and V hypertriglyceridemia. Intravenous injection of C-II-a (30 mg/kg) in apolipoprotein E–knockout mice resulted in a significant reduction of plasma cholesterol and triglycerides of 38 ± 6% and 85 ± 7%, respectively, at 4 hours. When coinjected with the 5A peptide (60 mg/kg), the C-II-a (30 mg/kg) peptide was found to completely block the hypertriglyceridemic effect of the 5A peptide in C57Bl/6 mice. In summary, C-II-a is a novel peptide based on apoC-II, which promotes cholesterol efflux and lipolysis and may therefore be useful for the treatment of apoC-II deficiency and other forms of hypertriglyceridemia. PMID:25395590

Association of triglycerides and new lipid markers with the incidence of hypertension in a Spanish cohort.

Science.gov (United States)

Sánchez-Íñigo, Laura; Navarro-González, David; Pastrana-Delgado, Juan; Fernández-Montero, Alejandro; Martínez, J Alfredo

2016-07-01

Triglycerides and high-density lipoprotein cholesterol (HDL-C) are known to be risk factors for cardiovascular disease. However, there has been limited knowledge on the relationship between triglycerides and incident hypertension. The associations of incident hypertension with triglycerides and triglycerides-related indices such as triglycerides to HDL-C ratio (TG/HDL-C) and triglyceride-glucose index (TyG) were evaluated. Data from 3637 participants from the Vascular Metabolic Clinica Universidad Navarra cohort were followed-up during a mean of 8.49 years. A Cox proportional hazard ratio with repeated measures analyses was performed to assess the risk of developing hypertension across the quintiles of triglycerides, TG/HDL-C ratio, and TyG index. The risk of developing hypertension was 47% and 73% greater for those in the fourth and fifth quintiles of triglycerides, after adjusting for age, sex, BMI, cigarette smoking, daily alcohol intake, lifestyle pattern, type 2 diabetes, antiaggregation therapy, low-density lipoprotein cholesterol, SBP, and DBP. In men, those in the top quintile of triglycerides, TG/HDL-C ratio or TyG index were two times more likely to develop hypertension than those in the bottom quintile. In women, the effect was attenuated although the risk of hypertension rose with increasing quintiles (P for trend triglycerides-related variables and incident hypertension independently of adiposity. This association was stronger than those observed for other commonly used lipid parameters or lipid ratios, such as the TC/HDL-C ratio. : http://links.lww.com/HJH/A620.

Triglycerides

Science.gov (United States)

What are triglycerides? Triglycerides are a type of fat. They are the most common type of fat in your body. They come from ... especially butter, oils, and other fats you eat. Triglycerides also come from extra calories. These are the ...

Acid Lipase Disease

Science.gov (United States)

... of Neurological Disorders and Stroke conducts and supports research to understand lipid storage diseases such as acid lipase deficiency and ... of Neurological Disorders and Stroke conducts and supports research to understand lipid storage diseases such as acid lipase deficiency and ...

Severe hypertriglyceridemia due to two novel loss-of-function lipoprotein lipase gene mutations (C310R/E396V) in a Chinese family associated with recurrent acute pancreatitis.

Science.gov (United States)

Lun, Yu; Sun, Xiaofang; Wang, Ping; Chi, Jingwei; Hou, Xu; Wang, Yangang

2017-07-18

Lipoprotein lipase (LPL) is widely expressed in skeletal muscles, cardiac muscles as well as adipose tissue and involved in the catabolism of triglyceride. Herein we have systematically characterized two novel loss-of-function mutations in LPL from a Chinese family in which afflicted members were manifested by severe hypertriglyceridemia and recurrent pancreatitis. DNA sequencing revealed that the proband was a heterozygote carrying a novel c.T928C (p.C310R) mutation in exon 6 of the LPL gene. Another member of the family was detected to be a compound heterozygote who along with the c.T928C mutation also carried a novel missense mutation c.A1187T (p.E396V) in exon 8 of the LPL gene. Furthermore, COS-1 cells were transfected with lentiviruses containing the mutant LPL genes. While C310R markedly reduced the overall LPL protein level, COS-1 cells carrying E396V or double mutations contained similar overall LPL protein levels to the wild-type. The specific activity of the LPL mutants remained at comparable magnitude to the wild-type. However, few LPL were detected in the culture medium for the mutants, suggesting that both mutations caused aberrant triglyceride catabolism. More specifically, E396V and double mutations dampened the transport of LPL to the cell surface, while for the C310R mutation, reducing LPL protein level might be involved. By characterizing these two novel LPL mutations, this study has expanded our understanding on the pathogenesis of familial hypertriglyceridemia (FHTG).

Implications of surface charge and curvature for the binding orientation of Thermomyces lanuginosus lipase on negatively charged or zwitterionic phospholipid vesicles as studied by ESR spectroscopy

DEFF Research Database (Denmark)

Hedin, E.M.K.; Høyrup, Lise Pernille Kristine; Patkar, S.A.

2005-01-01

fluorescence quenching efficiency between each spin-label positioned on TLL, and the lipid membrane. ESR exposure and fluorescence quenching data show that TILL associates closer to the negatively charged PG surface than the zwitterionic PC surface, and binds to both POPG LUV and POPC SUV predominantly through......The triglyceride lipase (EC 3.1.1.3) Thermomyces lanuginosus lipase (TLL) binds with high affinity to unilamellar phospholipid vesicles that serve as a diluent interface for both lipase and substrate, but it displays interfacial activation on only small and negatively charged such vesicles [Cajal......) spectroscopy in combination with site-directed spin-labeling [Hedin, E. M. K., et al. (2002) Biochemistry 41, 1418514196]. In our investigation, we have studied the interfacial orientation of TLL when bound to large unilamellar vesicles (LUV) consisting of POPG, and bound to SUV consisting of 1-palmitoyl-2...

The Effect of Tallow As Lipase Inducer on Total of Aspergillus Niger, Lipolitic Activity and Lipase Yield

Directory of Open Access Journals (Sweden)

Manik Eirry Sawitri

2012-02-01

Full Text Available The objectives of this research was to determined of tallow addition with different concentration as lipase Aspergillus niger inducer to total of A. niger, lipolitic activity and lipase yield. The result showed that tallow addition as inducer in the lipase A. niger production gave no significant effect on total of A. niger (5.3 x 107 – 1.7 x 108 cfu/gram in the medium. Tallow addition gave a highly significant effect on lipolytic activity and yield of lipase A. niger. Lipolytic activity ranged between 32.0354 – 53.1197 U/mg protein, while the yield of lipase was 6.6418–7.8941 µg/ml. The conclusion of this research was the addition of tallow for 8% as the lipase inducer of A. niger on lipase production was  more effective to obtain the optimal result. Keywords : Tallow, lipase, inducer, Aspergillus niger

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...

Excess abdominal adiposity remains correlated with altered lipid concentrations in healthy older women.

Science.gov (United States)

DiPietro, L; Katz, L D; Nadel, E R

1999-04-01

To determine associations between overall adiposity, absolute and relative abdominal adiposity, and lipid concentrations in healthy older women. Cross-sectional analysis of baseline data. Subjects were 21 healthy, untrained older women (71 +/- 1 y) entering a randomized, controlled aerobic training program. Overall adiposity was assessed by anthropometry and the body mass index (BMI=kg/m2). Absolute and relative abdominal adiposity was determined by computed tomography (CT) and circumference measures. Fasting serum lipid concentrations of total-, high density lipoprotein (HDL)-, and low density lipoprotein (LDL)-cholesterol (C) and triglycerides (TGs) were determined by standard enzymatic procedures. Compared to the measures of overall adiposity, we observed much stronger correlations between measures more specific to absolute or relative abdominal adiposity and lipid concentrations. Visceral fat area was the strongest correlate of HDL-C (r = -0.75; P HDL-C ratio (r = 0.86; P correlated with TGs (r = 0.54; P HDL-C (r= -0.69; P HDL-C ratio (r = 0.75; P adiposity remains an important correlate of lipid metabolism, even in healthy older women of normal weight. Thus, overall obesity is not a necessary condition for the correlation between excess abdominal fat and metabolic risk among postmenopausal women.

Activation of lipoprotein lipase by lipoprotein fractions of human serum.

Science.gov (United States)

Bier, D M; Havel, R J

1970-11-01

Triglycerides in fat emulsions are hydrolyzed by lipoprotein lipase only when they are "activated" by serum lipoproteins. The contribution of different lipoprotein fractions to hydrolysis of triglycerides in soybean oil emulsion was assessed by determining the quantity of lipoprotein fraction required to give half-maximal hydrolysis. Most of the activator property of whole serum from normolipidemic, postabsorptive subjects was in high density lipoproteins. Low density lipoproteins and serum from which all lipoprotein classes were removed had little or no activity. Also, little activator was present in guinea pig serum or in very low density poor serum from an individual with lecithin:cholesterol acyltransferase deficiency, both of which are deficient in high density lipoproteins. Human very low density lipoproteins are potent activators and are much more active than predicted from their content of high density lipoprotein-protein. Per unit weight of protein, very low density lipoproteins had 13 times the activity of high density lipoproteins. These observations suggest that one or more of the major apoproteins of very low density lipoproteins, present as a minor constituent of high density lipoproteins, may be required for the activation process.

High density lipoprotein is an inappropriate substrate for hepatic lipase in postmenopausal women.

Science.gov (United States)

Zago, Valeria; Miksztowicz, Verónica; Cacciagiú, Leonardo; Basilio, Francisco; Berg, Gabriela; Schreier, Laura

2012-12-24

HDL antiatherogenic effects would not only depend on its concentration but also on its biological quality. Hepatic lipase (HL) action on HDL acts in one of the last steps of reverse cholesterol transport. Cardiovascular risk increases after menopause, however HDL does not decrease even when HL is increased. We evaluated HDL capacity as a substrate of HL in healthy postmenopausal women (PMW). We studied 20 PMW (51-60 y) and 20 premenopausal (PreMW) (26-40 y). In fasting serum, lipid-lipoprotein profile and HDL composition were assessed. Optimal assay conditions for HDL/HL ex vivo incubation were established. Increasing HDL-triglyceride concentrations (0.015 to 0.20 mmol/l) were incubated with post-heparin plasma obtained from a single healthy donor as a source of HL. Free fatty acids were measured and kinetic parameters calculated: K(m)(app), inverse to enzyme affinity, and V(max). HDL composition in PMW exhibits triglyceride enrichment (p<0.001). Kinetic analysis revealed higher K(m)(app) in PMW [130 (40-380) vs 45 (20-91) mmol/l, p<0.0001)] correlating directly with HDL-triglycerides (r=0.7, p=0.0001). Catalytic efficiency, V(max)/K(m)(app) was reduced when compared to controls (p=0.0001). Triglyceride-enriched HDL from PMW constitutes a poor substrate for HL suggesting that this particle may not exert efficiently its antiatherogenic function, regardless of plasma concentration. Copyright © 2012 Elsevier B.V. All rights reserved.

Red algae (Gelidium amansii reduces adiposity via activation of lipolysis in rats with diabetes induced by streptozotocin-nicotinamide

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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.

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

OBJECTIVE: Glucose-dependent insulinotropic polypeptide (GIP) appears to have a role in lipid metabolism. Recently, we showed that GIP in combination with hyperinsulinemia and hyperglycemia increases triglyceride uptake in abdominal, subcutaneous adipose tissue in lean humans. It has been suggested...... 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...... to an oral glucose challenge: (i) NGT and (ii) IGT. Abdominal, subcutaneous adipose tissue lipid metabolism was studied by conducting measurements of arteriovenous concentrations of metabolites and regional adipose tissue blood flow (ATBF) during GIP (1.5 pmol kg(-1) min(-1)) in combination with a HI...

Bio F1B hamster: a unique animal model with reduced lipoprotein lipase activity to investigate nutrient mediated regulation of lipoprotein metabolism

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Cornish Marion L

2007-12-01

Full Text Available Abstract Background Bio F1B hamster is an inbred hybrid strain that is highly susceptible to diet-induced atherosclerosis. We previously reported that feeding a high fat fish oil diet to Bio F1B hamster caused severe hyperlipidaemia. In this study we compared the effects of various diets in the Bio F1B hamster and the Golden Syrian hamster, which is an outbred hamster strain to investigate whether genetic background plays an important role in dietary fat mediated regulation of lipoprotein metabolism. We further investigated the mechanisms behind diet-induced hyperlipidaemia in F1B hamster. Methods The Bio F1B and Golden Syrian hamsters, 8 weeks old, were fed high fat diets rich in either monounsaturated fatty acids, an n-6: n-3 ratio of 5 or a fish oil diet for 4 weeks. Animals were fasted overnight and blood and tissue samples were collected. Plasma was fractionated into various lipoprotein fractions and assayed for triacylglycerol and cholesterol concentrations. Plasma lipoprotein lipase activity was measured using radioisotope method. Microsomal triglyceride transfer protein activity was measured in the liver and intestine. Plasma apolipoproteinB48, -B100 and apolipoprotein E was measured using Western blots. Two-way ANOVA was used to determine the effect of diet type and animal strain. Results The fish oil fed F1B hamsters showed milky plasma after a 14-hour fast. Fish oil feeding caused accumulation of apolipoproteinB48 containing lipoprotein particles suggesting hindrance of triglyceride-rich lipoprotein clearance. There was no significant effect of diet or strain on hepatic or intestinal microsomal triglyceride transfer protein activity indicating that hyperlipidaemia is not due to an increase in the assembly or secretion of lipoprotein particles. F1B hamsters showed significantly reduced levels of lipoprotein lipase activity, which was inhibited by fish oil feeding. Conclusion Evidence is presented for the first time that alterations in

Supplementation of chitosan alleviates high-fat diet-enhanced lipogenesis in rats via adenosine monophosphate (AMP)-activated protein kinase activation and inhibition of lipogenesis-associated genes.

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Chiu, Chen-Yuan; Chan, Im-Lam; Yang, Tsung-Han; Liu, Shing-Hwa; Chiang, Meng-Tsan

2015-03-25

This study investigated the role of chitosan in lipogenesis in high-fat diet-induced obese rats. The lipogenesis-associated genes and their upstream regulatory proteins were explored. Diet supplementation of chitosan efficiently decreased the increased weights in body, livers, and adipose tissues in high-fat diet-fed rats. Chitosan supplementation significantly raised the lipolysis rate; attenuated the adipocyte hypertrophy, triglyceride accumulation, and lipoprotein lipase activity in epididymal adipose tissues; and decreased hepatic enzyme activities of lipid biosynthesis. Chitosan supplementation significantly activated adenosine monophosphate (AMP)-activated protein kinase (AMPK) phosphorylation and attenuated high-fat diet-induced protein expressions of lipogenic transcription factors (PPAR-γ and SREBP1c) in livers and adipose tissues. Moreover, chitosan supplementation significantly inhibited the expressions of downstream lipogenic genes (FAS, HMGCR, FATP1, and FABP4) in livers and adipose tissues of high-fat diet-fed rats. These results demonstrate for the first time that chitosan supplementation alleviates high-fat diet-enhanced lipogenesis in rats via AMPK activation and lipogenesis-associated gene inhibition.

Effects and Molecular Mechanism of GST-Irisin on Lipolysis and Autocrine Function in 3T3-L1 Adipocytes.

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Shanshan Gao

Full Text Available Irisin, which was recently identified as a myokine and an adipokine, transforms white adipose tissue to brown adipose tissue and has increasingly caught the attention of the medical and scientific community. However, the signaling pathway of irisin and the molecular mechanisms responsible for the lipolysis effect remain unclear. In this study, we established an efficient system for the expression and purification of GST-irisin in Escherichia coli. The biological activity of GST-irisin was verified using the cell counting kit-8 assay and by detecting the mRNA expression of uncoupling protein 1. Our data showed that GST-irisin regulates mRNA levels of lipolysis-related genes such as adipose triglyceride lipase and hormone-sensitive lipase and proteins such as the fatty acid-binding protein 4, leading to increased secretion of glycerol and decreased lipid accumulation in 3T3-L1 adipocytes. In addition, exogenous GST-irisin can increase its autocrine function in vitro by regulating the expression of fibronectin type III domain-containing protein 5. GST-irisin could regulate glucose uptake in 3T3-L1 adipocytes. Hence, we believe that recombinant GST-irisin could promote lipolysis and its secretion in vitro and can potentially prevent obesity and related metabolic diseases.

Differential expression of genes associated with lipid metabolism in longissimus dorsi of Korean bulls and steers.

Science.gov (United States)

Bong, Jin Jong; Jeong, Jin Young; Rajasekar, Panchamoorthy; Cho, Young Moo; Kwon, Eung Gi; Kim, Hyeong Cheol; Paek, Bong Hyun; Baik, Myunggi

2012-07-01

The objective of this study was to compare expression of genes associated with lipid deposition and removal between bulls and steers in the longissimus dorsi muscle (LM) tissue of Korean cattle. Castration increased the expression of lipid uptake lipoprotein lipase, fatty acid translocase, and fatty acid transport protein 1 in LM. Castration increased lipogenic gene expression of both acetyl-CoA carboxylase and fatty acid synthase. In contrast, castration downregulated lipolytic gene expression of both adipose triglyceride lipase (ATGL) and monoglyceride lipase. Steers showed higher expression levels of insulin signaling phospho-v-akt murine thymoma viral oncogene homolog 1 than bulls but lower protein levels of nuclear Forkhead box O 1 (FoxO1) than bulls, suggesting that increased insulin signaling following castration decreases nuclear FoxO1 levels, leading to downregulation of ATGL gene expression. These findings suggest that castration contributes to increases in lipid uptake and lipogenesis and a decrease in lipolysis, resulting in improved marbling. Copyright © 2012 Elsevier Ltd. All rights reserved.

Activity and stability of immobilized lipases in lipase-catalyzed modification of peanut oil

OpenAIRE

Soumanou Mohamed M.; Edorh Aleodjrodo P.; Bornscheuer Uwe T.

2004-01-01

Fatty acid release during lipolysis of peanut oil using microbial free and immobilized lipases in aqueous media was developed. Immobilized lipase from Rhizomucor miehei (RML) gave the best result from its ability to clive different fatty acids from peanut oil in such media. In organic solvent, interesterification of peanut oil with tricaprylin using immobilized lipases from RML, Chromobacterium viscosum (CVL) and Candida rugosa (CRL) was performed. The best substrate molar ratio of tricapryli...

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. Copyright 2010 Elsevier Inc. All rights reserved.

Effect of physical exercise on blood lipids and adipose tissue composition in young healthy men

NARCIS (Netherlands)

Danner, S. A.; Wieling, W.; Havekes, L.; Leuven, J. G.; Smit, E. M.; Dunning, A. J.

1984-01-01

In a prospective, controlled study, the influence of strenuous physical exercise on plasma total cholesterol, HDL cholesterol, apolipoprotein A-I, total triglycerides and fatty acid composition of adipose tissue was studied during 7 months of training in 15 senior oarsmen and 21 controls matched for

Organic Solvent Tolerant Lipases and Applications

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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.

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. Copyright © 2016. Published by Elsevier Ltd.

FRAKSINASI ENZIM LIPASE DARI ENDOSPERM KELAPA DENGAN METODE SALTING OUT (Lipase fractionation of Coconut Endosperm by Salting out Method

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Moh. Su'i

2014-02-01

Full Text Available This research learns about fractionation of lipases activity from coconut endosperm by using ammonium sulphate of 0–15%; 15-30 %, 30–45 %, 45–60 %, 60–75 % and 75–90 %. The results showed that the fractions of 0–15% ; 30–45 %, 45–60 % and 60–75 % have lipase activity. Meanwhile, the highest activity was fractions of 60-75%. fractions of 15-30% and 75-90%  have no lipase enzym activity. Molecule weigh of lipase enzyme was 72 kDa. Keywords: Lipases, endosperm, coconut, fractionation, ammonium sulphate   ABSTRAK Penelitian ini mempelajari fraksinasi enzim lipase dari endosperm kelapa menggunakan ammonium sulfat. fraksinasi dilakukan dengan variasi konsentrasi ammonium sulfat 0–15% ; 15-30%; 30–45 %, 45–60 %, 60–75 % dan 75–90 %. Hasil penelitian menunjukkan bahwa enzim lipase terdapat pada fraksi 0–15% ; 30–45 %, 45–60 % dan fraksi 60–75 % dengan aktivitas enzim tertinggi pada fraksi 60-75%. Sedangkan fraksi 15-30% dan 75-90% tidak ada enzim lipase. Berat molekul enzim lipase pada semua fraksi 72 kDa. Kata kunci: Lipase, endosperm, fraksinasi, ammonium sulfat

Brain insulin controls adipose tissue lipolysis and lipogenesis

Science.gov (United States)

Scherer, Thomas; O’Hare, James; Diggs-Andrews, Kelly; Schweiger, Martina; Cheng, Bob; Lindtner, Claudia; Zielinski, Elizabeth; Vempati, Prashant; Su, Kai; Dighe, Shveta; Milsom, Thomas; Puchowicz, Michelle; Scheja, Ludger; Zechner, Rudolf; Fisher, Simon J.; Previs, Stephen F.; Buettner, Christoph

2011-01-01

SUMMARY White adipose tissue (WAT) dysfunction plays a key role in the pathogenesis of type 2 diabetes (DM2). Unrestrained WAT lipolysis results in increased fatty acid release leading to insulin resistance and lipotoxicity, while impaired de novo lipogenesis in WAT decreases the synthesis of insulin sensitizing fatty acid species like palmitoleate. Here we show that insulin infused into the mediobasal hypothalamus (MBH) of Sprague Dawley rats increases WAT lipogenic protein expression, and inactivates hormone sensitive lipase (Hsl) and suppresses lipolysis. Conversely, mice that lack the neuronal insulin receptor exhibit unrestrained lipolysis and decreased de novo lipogenesis in WAT. Thus, brain and in particular hypothalamic insulin action play a pivotal role in WAT functionality. PMID:21284985

Lipase kinetics: hydrolysis of triacetin by lipase from Candida cylindracea in a hollow-fiber membrane reactor

NARCIS (Netherlands)

Guit, R.P.M.; Kloosterman, M.; Meindersma, G.W.; Mayer, M.; Meijer, E.M.

1991-01-01

The aptitude of a hollow-fiber membrane reactor to det. lipase kinetics was investigated using the hydrolysis of triacetin catalyzed by lipase from C. cylindracea as a model system. The binding of the lipase to the membrane appears not to be very specific (surface adsorption), and probably its

OPTIMASI ISOLASI LIPASE INDIGENOUS BIJI KAKAO (Theobroma cacao L. The Optimizing of Isolation of Cocoa Bean Indogenous Lipase (Theobroma cacao L.

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I D. G. Mayun Permana

2012-05-01

Full Text Available The aim of the research is to optimize the isolation method of cocoa bean lipase. The research is held by determining the position of lipase on cocoa bean, varying extraction medium and isolation process. The result shows that the lipase of cocoa bean is   cytosolic enzyme. The defatting process do not increase the lipase activity. Polyphenols inhibit the lipase activity, so that removal of the polyphenol will increase the activity. Blocking the polyphenol with polyvinilpolypirrolidone (PVPP will also increase the activity.The optimum consentration of PVPP is 8 %. The lipase activity will reach the highest when homogenized for 10 menit at 10,000 rpm. The best medium extraction for lipase isolation is 0.15 M phosphate buffer pH 7.5 containing sucrose 0.6 M and CaCl  1.0 mM.   ABSTRAK Penelitian ini bertujuan untuk mengoptimasi isolasi lipase indigenous biji kakao. Optimasi diawali dengan menentukan keberadaan lipase kemudian optimasi medium ekstraksi dan proses ekstraksi. Hasil penelitian menunjukkan bahwa lipase berada dalam sitosol. Penghilangan lemak tidak meningkatkan aktivitas lipase. Senyawa polifenol menghambat aktivitas lipase dan penghilangan polifenol dapat meningkatkan aktivitas lipase. Polyvinilpolypirrolidone (PVPP dapat menghambat polifenol sehingga dapat meningkatkan aktivitas lipase. Konsentrasi PVPP optimum adalah 8 % dari berat biji kakao. Proses homogenisasi optimum diperoleh dalam waktu 10 menit pada kecepatan 10.000 rpm. Medium ekstraksi untuk isolasi lipase biji kakao terbaik adalah bufer fosfat 0,15 M  dan pH 7,5 yang mengandung sukrosa 0,6 M dan 1,0 mM CaCl .

Red algae (Gelidium amansii) reduces adiposity via activation of lipolysis in rats with diabetes induced by streptozotocin-nicotinamide.

Science.gov (United States)

Yang, Tsung-Han; Yao, Hsien-Tsung; Chiang, Meng-Tsan

2015-12-01

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. Copyright © 2015. Published by Elsevier B.V.

Familial lipoprotein lipase deficiency

Science.gov (United States)

... lack an enzyme called lipoprotein lipase. Without this enzyme, the body cannot break down fat from digested food. Fat particles called chylomicrons build up in the blood. Risk factors include a family history of lipoprotein lipase deficiency. The condition is usually ...

PCSK9 and triglyceride-rich lipoprotein metabolism.

Science.gov (United States)

Druce, I; Abujrad, H; Ooi, T C

2015-07-20

Pro-protein convertase subtilisin-kexin 9 (PCSK9) is known to affect low-density lipoprotein (LDL) metabolism, but there are indications from several lines of research that it may also influence the metabolism of other lipoproteins, especially triglyceride-rich lipoproteins (TRL). This review summarizes the current data on this possible role of PCSK9. A link between PCSK9 and TRL has been suggested through the demonstration of (1) a correlation between plasma PCSK9 and triglyceride (TG) levels in health and disease, (2) a correlation between plasma PCSK9 and markers of carbohydrate metabolism, which is closely related to TG metabolism, (3) an effect of TG-lowering fibrate therapy on plasma PCSK9 levels, (4) an effect of PCSK9 on postprandial lipemia, (5) an effect of PCSK9 on adipose tissue biology, (6) an effect of PCSK9 on apolipoprotein B production from the liver and intestines, (7) an effect of PCSK9 on receptors other than low density lipoprotein receptor (LDLR) that are involved in TRL metabolism, and (8) an effect of anti-PCSK9 therapy on serum TG levels. The underlying mechanisms are unclear but starting to emerge. © 2015 the Journal of Biomedical Research. All rights reserved.

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.

CTRP3 attenuates diet-induced hepatic steatosis by regulating triglyceride metabolism.

Science.gov (United States)

Peterson, Jonathan M; Seldin, Marcus M; Wei, Zhikui; Aja, Susan; Wong, G William

2013-08-01

CTRP3 is a secreted plasma protein of the C1q family that helps regulate hepatic gluconeogenesis and is downregulated in a diet-induced obese state. However, the role of CTRP3 in regulating lipid metabolism has not been established. Here, we used a transgenic mouse model to address the potential function of CTRP3 in ameliorating high-fat diet-induced metabolic stress. Both transgenic and wild-type mice fed a high-fat diet showed similar body weight gain, food intake, and energy expenditure. Despite similar adiposity to wild-type mice upon diet-induced obesity (DIO), CTRP3 transgenic mice were strikingly resistant to the development of hepatic steatosis, had reduced serum TNF-α levels, and demonstrated a modest improvement in systemic insulin sensitivity. Additionally, reduced hepatic triglyceride levels were due to decreased expression of enzymes (GPAT, AGPAT, and DGAT) involved in triglyceride synthesis. Importantly, short-term daily administration of recombinant CTRP3 to DIO mice for 5 days was sufficient to improve the fatty liver phenotype, evident as reduced hepatic triglyceride content and expression of triglyceride synthesis genes. Consistent with a direct effect on liver cells, recombinant CTRP3 treatment reduced fatty acid synthesis and neutral lipid accumulation in cultured rat H4IIE hepatocytes. Together, these results establish a novel role for CTRP3 hormone in regulating hepatic lipid metabolism and highlight its protective function and therapeutic potential in attenuating hepatic steatosis.

Obesity and chronic stress are able to desynchronize the temporal pattern of serum levels of leptin and triglycerides.

Science.gov (United States)

de Oliveira, Carla; Scarabelot, Vanessa Leal; de Souza, Andressa; de Oliveira, Cleverson Moraes; Medeiros, Liciane Fernandes; de Macedo, Isabel Cristina; Marques Filho, Paulo Ricardo; Cioato, Stefania Giotti; Caumo, Wolnei; Torres, Iraci L S

2014-01-01

Disruption of the circadian system can lead to metabolic dysfunction as a response to environmental alterations. This study assessed the effects of the association between obesity and chronic stress on the temporal pattern of serum levels of adipogenic markers and corticosterone in rats. We evaluated weekly weight, delta weight, Lee index, and weight fractions of adipose tissue (mesenteric, MAT; subcutaneous, SAT; and pericardial, PAT) to control for hypercaloric diet-induced obesity model efficacy. Wistar rats were divided into four groups: standard chow (C), hypercaloric diet (HD), stress plus standard chow (S), and stress plus hypercaloric diet (SHD), and analyzed at three time points: ZT0, ZT12, and ZT18. Stressed animals were subjected to chronic stress for 1h per day, 5 days per week, during 80 days. The chronic exposure to a hypercaloric diet was an effective model for the induction of obesity and metabolic syndrome, increasing delta weight, Lee index, weight fractions of adipose tissue, and triglycerides and leptin levels. We confirmed the presence of a temporal pattern in the release of triglycerides, corticosterone, leptin, and adiponectin in naïve animals. Chronic stress reduced delta weight, MAT weight, and levels of triglycerides, total cholesterol, and leptin. There were interactions between chronic stress and obesity and serum total cholesterol levels, between time points and obesity and adiponectin and corticosterone levels, and between time points and chronic stress and serum leptin levels. In conclusion, both parameters were able to desynchronize the temporal pattern of leptin and triglyceride release, which could contribute to the development of metabolic diseases such as obesity and metabolic syndrome. Copyright © 2013 Elsevier Inc. All rights reserved.

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. Copyright © 2016 Elsevier Ltd. All rights reserved.

Uptake and metabolism of structured triglyceride by Caco-2 cells: reversal of essential fatty acid deficiency.

Science.gov (United States)

Spalinger, J H; Seidman, E G; Lepage, G; Ménard, D; Gavino, V; Levy, E

1998-10-01

Structured lipids have been proposed as efficient vehicles for the supplementation of essential fatty acids (EFA) to patients with malabsorption. We investigated how a novel structured triglyceride (STG), containing purely octanoic acid in the sn-1/sn-3 and [14C]linoleic acid in the sn-2 positions, was incorporated into different lipid classes in Caco-2 cells. We also evaluated the contribution of gastric lipase in the uptake and metabolism of [14C]linoleic acid from the STG. We furthermore determined the potential of the STG to correct EFA deficiency induced in Caco-2 cells. The absorption of STG by Caco-2 cells was significantly greater compared with that of triolein. The addition of human gastric lipase significantly enhanced cellular uptake of the labeled substrate, reflecting the stereoselectivity of gastric lipase to hydrolyze medium chain FA. Analysis of the intracellular lipids synthesized revealed a predominance of phospholipids-monoglycerides. Most of the radioactivity in the lipoproteins isolated from Caco-2 cells was recovered in TG-rich lipoproteins (45%) and to a lesser extent in the high-density lipoprotein (36%) and low-density lipoprotein (17%) fractions. The administration of STG to Caco-2 cells rendered EFA deficient produced a marked increase of the cellular level of linoleic and arachidonic acids. This resulted in a lower ratio of 20:3(n-9) to 20:4(n-6), reflecting the correction of EFA deficiency in Caco-2 cells. Our data demonstrate that STG, in the presence of gastric lipase, have beneficial effects on lipid incorporation, lipoprotein production, and EFA status, utilizing Caco-2 cells as a model of EFA deficiency.

Potencial de biocatálise enantiosseletiva de lipases microbianas Potential of enantioselective biocatalysis by microbial lipases

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Patrícia de O. Carvalho

2005-08-01

Full Text Available 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 from Aspergillus niger showed the highest activity (18.2 U/mL and was highly thermostable, retaining 90% and 60% activity at 50 ºC and 60 ºC after 1 hour, respectively. In organic medium, this lipase provided the best results in terms of enantiomeric excess of the (S-active acid (ee = 6.1% and conversion value (c = 20% in the esterification of (R,S-ibuprofen with 1-propanol in isooctane. The esterification reaction of the racemic mixture of (R,S-2-octanol with decanoic acid proceeded with high enantioselectivity when lipase from Aspergillus niger (E = 13.2 and commercial lipase from Candida antarctica (E = 20 were employed.

Lipase-catalyzed biodiesel production from waste activated bleaching earth as raw material in a pilot plant.

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Park, Enoch Y; Sato, Masayasu; Kojima, Seiji

2008-05-01

The production of fatty acid methyl esters (FAMEs) from waste activated bleaching earth (ABE) discarded by the crude oil refining industry using lipase from Candida cylindracea was investigated in a 50-L pilot plant. Diesel oil or kerosene was used as an organic solvent for the transesterification of triglycerides embedded in the waste ABE. When 1% (w/w) lipase was added to waste ABE, the FAME content reached 97% (w/w) after reaction for 12 h at 25 degrees C with an agitation rate of 30 rpm. The FAME production rate was strongly dependent upon the amount of enzyme added. Mixtures of FAME and diesel oil at ratios of 45:55 (BDF-45) and 35:65 (BDF-35) were assessed and compared with the European specifications for biodiesel as automotive diesel fuel, as defined by pr EN 14214. The biodiesel quality of BDF-45 met the EN 14214 standard. BDF-45 was used as generator fuel, and the exhaust emissions were compared with those of diesel oil. The CO and SO2 contents were reduced, but nitrogen oxide emission increased by 10%. This is the first report of a pilot plant study of lipase-catalyzed FAME production using waste ABE as a raw material. This result demonstrates a promising reutilization method for the production of FAME from industrial waste resources containing vegetable oils for use as a biodiesel fuel.

Application of alkaline thermo-stable lipase(s) enzyme produced from irradiated microbial isolate in the field of detergent technology

International Nuclear Information System (INIS)

Ahmed, O.E.A.M.S

2010-01-01

Due to continuous demand for manufacture of high quality, low coast industrial detergents containing lipolytic enzymes and due to continuous accumulation of enviro-agro-industrial wastes which are good and suitable conditions for growth and reproduction of pathogenic microorganisms, our study aims at isolating thermoalkalophilic lipase producer microorganisms from enviro-agro-industrial wastes and selection of the most potent isolate for studying physiological conditions controlling enzyme formation also purification characterization and some applications on purified and crude enzyme as bio-detergent. Some environmental and industrial wastes were collected from different places. The industrial wastes include, cotton seed, soyabean, sun flower, lin seed and olive oil wastes. Environmental wastes include poultry and fish wastes, all these wastes were dried at 70 degree C, grounded and used for isolation of microorganisms and lipase(s) production.Nine thermoalkalophilic bacterial isolates were isolated from enviro-agro-industrial wastes at ph 11.5 and 70 degree C. They were purified and screening for their ability of thermoalkalo-stable lipase(s) formation, this is followed by examining the effect of different nutritional media and exposure of bacterial isolates to different doses of gamma irradiation and the influence of these radiation on lipase(s) productivity by these isolates. From the results it was found that.1- The most potent lipase(s) forming bacterial isolates were isolates number B 2 and B 3 which cultivated on medium A amended with fish-wastes as being the best nutritional medium for enzyme formation. 2-Bacterial isolate B 2 finally was selected as being the most potent lipase(s) forming bacterial isolate cultivated on fish-wastes and yeast extract (in tap water) and identified according to key's of Bergey Manual of Systematic Bacteriology (1984) as being Bacillus brevis B 2 .The optimum culture conditions for maximum biosynthesis of extracellular lipase(s

Perilipin 1 Mediates Lipid Metabolism Homeostasis and Inhibits Inflammatory Cytokine Synthesis in Bovine Adipocytes.

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Zhang, Shiqi; Liu, Guowen; Xu, Chuang; Liu, Lei; Zhang, Qiang; Xu, Qiushi; Jia, Hongdou; Li, Xiaobing; Li, Xinwei

2018-01-01

Dairy cows with ketosis displayed lipid metabolic disorder and high inflammatory levels. Adipose tissue is an active lipid metabolism and endocrine tissue and is closely related to lipid metabolism homeostasis and inflammation. Perilipin 1 (PLIN1), an adipocyte-specific lipid-coated protein, may be involved in the above physiological function. The aim of this study is to investigate the role of PLIN1 in lipid metabolism regulation and inflammatory factor synthesis in cow adipocytes. The results showed that PLIN1 overexpression upregulated the expression of fatty acid and triglyceride (TAG) synthesis molecule sterol regulator element-binding protein-1c (SREBP-1c) and its target genes, diacylglycerol acyltransferase (DGAT) 1, and DGAT2, but inhibited the expression of lipolysis enzymes hormone-sensitive lipase (HSL) and CGI-58 for adipose triglyceride lipase (ATGL), thus augmenting the fatty acids and TAG synthesis and inhibiting lipolysis. Importantly, PLIN1 overexpression inhibited the activation of the NF-κB inflammatory pathway and decreased the expression and content of tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1β), and interleukin 6 (IL-6) induced by lipopolysaccharide. Conversely, PLIN1 silencing inhibited TAG synthesis, promoted lipolysis, and overinduced the activation of the NF-κB inflammatory pathway in cow adipocytes. In ketotic cows, the expression of PLIN1 was markedly decreased, whereas lipid mobilization, NF-κB pathway, and downstream inflammatory cytokines were overinduced in adipose tissue. Taken together, these results indicate that PLIN1 can maintain lipid metabolism homeostasis and inhibit the NF-κB inflammatory pathway in adipocytes. However, low levels of PLIN1 reduced the inhibitory effect on fat mobilization, NF-κB pathway, and inflammatory cytokine synthesis in ketotic cows.

Perilipin 1 Mediates Lipid Metabolism Homeostasis and Inhibits Inflammatory Cytokine Synthesis in Bovine Adipocytes

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Shiqi Zhang

2018-03-01

Full Text Available Dairy cows with ketosis displayed lipid metabolic disorder and high inflammatory levels. Adipose tissue is an active lipid metabolism and endocrine tissue and is closely related to lipid metabolism homeostasis and inflammation. Perilipin 1 (PLIN1, an adipocyte-specific lipid-coated protein, may be involved in the above physiological function. The aim of this study is to investigate the role of PLIN1 in lipid metabolism regulation and inflammatory factor synthesis in cow adipocytes. The results showed that PLIN1 overexpression upregulated the expression of fatty acid and triglyceride (TAG synthesis molecule sterol regulator element-binding protein-1c (SREBP-1c and its target genes, diacylglycerol acyltransferase (DGAT 1, and DGAT2, but inhibited the expression of lipolysis enzymes hormone-sensitive lipase (HSL and CGI-58 for adipose triglyceride lipase (ATGL, thus augmenting the fatty acids and TAG synthesis and inhibiting lipolysis. Importantly, PLIN1 overexpression inhibited the activation of the NF-κB inflammatory pathway and decreased the expression and content of tumor necrosis factor alpha (TNF-α, interleukin 1 beta (IL-1β, and interleukin 6 (IL-6 induced by lipopolysaccharide. Conversely, PLIN1 silencing inhibited TAG synthesis, promoted lipolysis, and overinduced the activation of the NF-κB inflammatory pathway in cow adipocytes. In ketotic cows, the expression of PLIN1 was markedly decreased, whereas lipid mobilization, NF-κB pathway, and downstream inflammatory cytokines were overinduced in adipose tissue. Taken together, these results indicate that PLIN1 can maintain lipid metabolism homeostasis and inhibit the NF-κB inflammatory pathway in adipocytes. However, low levels of PLIN1 reduced the inhibitory effect on fat mobilization, NF-κB pathway, and inflammatory cytokine synthesis in ketotic cows.

New eutectic ionic liquids for lipase activation and enzymatic preparation of biodiesel†

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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

Obesity-induced diet leads to weight gain, systemic metabolic alterations, adipose tissue inflammation, hepatic steatosis, and oxidative stress in gerbils (Meriones unguiculatus

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Luciana L.A. Ventura

2017-03-01

Full Text Available Background Nowadays, the number of obese people in the world has reached alarming proportions. During the expansion of adipose tissue, a number of functions such as activation and release of cytokines and hormones may be affected. This leads the body to a pro-inflammatory pattern, which may affect the proper functioning of many tissues. Thus, studying the mechanisms by which obesity induces physiological disorders is necessary, and may be facilitated by the use of animal models, in particular rodents. We sought to characterize the metabolic and adipose tissue changes resulting from a diet rich in fats and simple sugars in gerbils. Methods We divided 14 gerbils into two experimental groups that received a diet rich in simple carbohydrates and fats with 5,86 kcal/g (OB, n = 7 or a standard diet with 4.15 kcal/g (CT; n = 7 for 11 weeks. The animals had free access to water and food. The animal weight and food consumption were measured weekly. Blood, adipose tissue and liver of each animal were collected at the end of experiment. The following parameters were determined: cholesterol (COL, triglycerides (TGL and glycemia (GLI in the plasma; cytokines (IL-6, IL-10 and TNF-α and hormones (adiponectin and leptin in adipose tissue; activity of superoxide dismutase (SOD and catalase (CAT, extraction and differentiation of fat and histology in liver. Results The consumption of a diet rich in simple carbohydrates and fats led to increased total body weight and increased relative weights of liver and adipose tissue. In addition, we observed increased fasting glucose levels and circulating triglycerides, along with high TNF-α production in adipose tissue and increased total fat, cholesterol and triglyceride contents in the liver, contributing to higher intensity of hepatic steatosis. On the other hand, the animals of this group showed depletion in the enzyme activity of SOD and CAT in the liver, as well as reduction of IL-10 and adiponectin levels in

Lipase Test: MedlinePlus Lab Test Information

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... page: https://medlineplus.gov/labtests/lipasetest.html Lipase Test To use the sharing features on this page, please enable JavaScript. What is a lipase test? Lipase is a type of protein made by ...

Visceral adiposity index as an indicator of cardiometabolic risk in patients treated for craniopharyngioma.

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Ferraù, Francesco; Spagnolo, Federica; Cotta, Oana Ruxandra; Cannavò, Laura; Alibrandi, Angela; Russo, Giuseppina Tiziana; Aversa, Tommaso; Trimarchi, Francesco; Cannavò, Salvatore

2017-11-01

Craniopharyngioma is associated with metabolic alterations leading to increased cardiovascular mortality. Recently, the visceral adiposity index has been proposed as a marker of visceral adipose tissue dysfunction and of the related cardiometabolic risk. The role of the visceral adiposity index has never been explored in craniopharyngioma patients. We assessed the cardiometabolic risk on the basis of the visceral adiposity index in craniopharyngioma patients. We evaluated data of 24 patients treated for craniopharyngioma in a single-centre. We investigated the relationship among patients' clinical and biochemical features, cardiovascular risk -assessed by the Framingham and the atherosclerotic cardiovascular disease risk scores-, visceral adiposity index and adipose tissue dysfunction severity. Increased visceral adiposity index was found in 8 patients (33%). Adipose tissue dysfunction resulted to be severe, moderate or mild in 5, 2 and 1 cases. Increased visceral adiposity index significantly correlated with the occurrence of metabolic syndrome (p 0.027), IRI (p 0.001), triglycerides (p < 0.001), HOMA-IR (p < 0.001) and with lower ISI-Matsuda (p 0.005) and HDL-cholesterol (p < 0.001). Higher degree of adipose tissue dysfunction associated with increased insulin resistance. No gender difference was found for visceral adiposity index, adipose tissue dysfunction severity, and cardiovascular risk scores. Patients with adulthood onset craniopharyngioma showed higher Framingham risk score (p 0.004), atherosclerotic cardiovascular disease 10-year (p < 0.001) and lifetime (p 0.018) risk scores than those with childhood onset disease. Visceral adiposity index is increased in one third of our patients with craniopharyngioma, even if metabolic syndrome does not occur. Increased visceral adiposity index and adipose tissue dysfunction severity correlate with insulin sensitivity parameters, do not correlate with Framingham or atherosclerotic cardiovascular

21 CFR 184.1415 - Animal lipase.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Animal lipase. 184.1415 Section 184.1415 Food and... 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...

Radioisotopic method for the measurement of lipolysis in small samples of human adipose tissue

International Nuclear Information System (INIS)

Leibel, R.L.; Hirsch, J.; Berry, E.M.; Gruen, R.K.

1984-01-01

To facilitate the study of adrenoreceptor response in small needle biopsy samples of human subcutaneous adipose tissue, we developed a dual radioisotopic technique for measuring lipolysis rate. Aliquots (20-75 mg) of adipose tissue fragments were incubated in a buffered albumin medium containing [ 3 H]palmitate and [ 14 C]glucose, each of high specific activity. In neutral glycerides synthesized in this system, [ 14 C]glucose is incorporated exclusively into the glyceride-glycerol moiety and 3 H appears solely in the esterified fatty acid. Alpha-2 and beta-1 adrenoreceptor activation of tissue incubated in this system does not alter rates of 14 C-labeled glyceride accumulation, but does produce a respective increase or decrease in the specific activity of fatty acids esterified into newly synthesized glycerides. This alteration in esterified fatty acid specific activity is reflected in the ratio of 14 C: 3 H in newly synthesized triglycerides extracted from the incubated adipose tissue. There is a high correlation (r . 0.90) between the 14 C: 3 H ratio in triglycerides and the rate of lipolysis as reflected in glycerol release into the incubation medium. The degree of adrenoreceptor activation by various concentrations of lipolytic and anti-lipolytic substances can be assessed by comparing this ratio in stimulated tissue to that characterizing unstimulated tissue or the incubation medium. This technique permits the study of very small, unweighed tissue biopsy fragments, the only limitation on sensitivity being the specific activity of the medium glucose and palmitate. It is, therefore, useful for serial examinations of adipose tissue adrenoreceptor dose-response characteristics under a variety of clinical circumstances

Effects of a ketogenic diet on adipose tissue, liver, and serum biomarkers in sedentary rats and rats that exercised via resisted voluntary wheel running.

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Holland, Angelia Maleah; Kephart, Wesley C; Mumford, Petey W; Mobley, Christopher Brooks; Lowery, Ryan P; Shake, Joshua J; Patel, Romil K; Healy, James C; McCullough, Danielle J; Kluess, Heidi A; Huggins, Kevin W; Kavazis, Andreas N; Wilson, Jacob M; Roberts, Michael D

2016-08-01

We investigated the effects of different diets on adipose tissue, liver, serum morphology, and biomarkers in rats that voluntarily exercised. Male Sprague-Dawley rats (∼9-10 wk of age) exercised with resistance-loaded voluntary running wheels (EX; wheels loaded with 20-60% body mass) or remained sedentary (SED) over 6 wk. EX and SED rats were provided isocaloric amounts of either a ketogenic diet (KD; 20.2%-10.3%-69.5% protein-carbohydrate-fat), a Western diet (WD; 15.2%-42.7-42.0%), or standard chow (SC; 24.0%-58.0%-18.0%); n = 8-10 in each diet for SED and EX rats. Following the intervention, body mass and feed efficiency were lowest in KD rats, independent of exercise (P diets [total acetyl coA carboxylase (ACC), CD36, and CEBPα or phosphorylated NF-κB/p65, AMPKα, and hormone-sensitive lipase (HSL)], although EX unexpectedly altered some OMAT markers (i.e., higher ACC and phosphorylated NF-κB/p65, and lower phosphorylated AMPKα and phosphorylated HSL). Liver triglycerides were greatest in WD rats (P < 0.05), and liver phosphorylated NF-κB/p65 was lowest in KD rats (P < 0.05). Serum insulin, glucose, triglycerides, and total cholesterol were greater in WD and/or SC rats compared with KD rats (P < 0.05), and serum β-hydroxybutyrate was greater in KD vs. SC rats (P < 0.05). In conclusion, KD rats presented a healthier metabolic profile, albeit the employed exercise protocol minimally impacts any potentiating effects that KD has on fat loss. Copyright © 2016 the American Physiological Society.

VLDL hydrolysis by hepatic lipase regulates PPARδ transcriptional responses.

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Jonathan D Brown

Full Text Available 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.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.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 into specific lipid mediators and pathways of lipid

Potential Lipid-Lowering Effects of Eleusine indica (L) Gaertn. Extract on High-Fat-Diet-Induced Hyperlipidemic Rats.

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Ong, Siew Ling; Nalamolu, Koteswara Rao; Lai, How Yee

2017-01-01

� 5.68%).The acute oral toxicity of E. indica hexane extract on animal model falls into Globally Harmonized System Category 5 (low hazard), since mortality, clinical toxicity symptoms, gross pathologic, or histopathologic damage was not observed.The hexane extract of E. indica had significantly reduced the body weight and improved serum lipid profile, with reduction in serum triglycerides, total cholesterol, low-density lipoprotein, and elevation in high-density lipoprotein when comparing against the high-fat diet control group.Microscopic evaluation on histologic slides of liver and adipose tissues suggested that E. indica hexane extract had greatly improved liver steatosis and adipose tissue hypertrophy in high-fat diet control group. Abbreviation used: ALT: Alanine transaminase; AST: Aspartate transaminase; B-Ei: Butanol extract of E. indica ; DCM-Ei: Dichloromethane extract of E. indica ; EA-Ei: Ethyl acetate extract of E. indica ; GHS: Globally Harmonized System; HDL: High-density lipoprotein; H-Ei: Hexane extract of E. indica ; HFD: High-fat diet; HPLC: High-performance liquid chromatography; LDL: Low-density lipoprotein; NFD: Normal fed diet; PPL: Porcine pancreatic lipase; SEM: Standard error of mean; SD: Standard deviation; TC: Total cholesterol; TG: Triglycerides; W-Ei: Water extract of E. indica .

Triglycerides: A reappraisal.

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Wiesner, Philipp; Watson, Karol E

2017-08-01

Elevated cholesterol levels are clearly independently associated with adverse cardiovascular events. Another class of lipid particles, triglycerides, is also abundant in the human body and has been found in atherosclerotic plaques. Recent observational studies have demonstrated an association between elevated triglyceride levels and increased risk for future cardiovascular events. With this knowledge and the discovery of effective agents to lower triglyceride levels, the management of triglycerides is currently undergoing a renaissance. Unfortunately, no randomized, controlled clinical trials have been completed to date, proving that lowering triglycerides will reduce cardiovascular events. In this review we highlight some of the evidence that led to this stage and discuss the current data on pharmacologic intervention of triglyceride levels and the effect on clinical outcomes. Lastly, we want to give the reader insight on what the most recent lipid guidelines state about clinical triglyceride management, mention new pharmacological agents, and highlight the clinical evidence for safe and effective lowering of triglycerides levels with life style modification. Copyright © 2017. Published by Elsevier Inc.

Adipocyte differentiation-related protein promotes lipid accumulation in goat mammary epithelial cells.

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Shi, H B; Yu, K; Luo, J; Li, J; Tian, H B; Zhu, J J; Sun, Y T; Yao, D W; Xu, H F; Shi, H P; Loor, J J

2015-10-01

Milk fat originates from the secretion of cytosolic lipid droplets (CLD) synthesized within mammary epithelial cells. Adipocyte differentiation-related protein (ADRP; gene symbol PLIN2) is a CLD-binding protein that is crucial for synthesis of mature CLD. Our hypothesis was that ADRP regulates CLD production and metabolism in goat mammary epithelial cells (GMEC) and thus plays a role in determining milk fat content. To understand the role of ADRP in ruminant milk fat metabolism, ADRP (PLIN2) was overexpressed or knocked down in GMEC using an adenovirus system. Immunocytochemical staining revealed that ADRP localized to the surface of CLD. Supplementation with oleic acid (OA) enhanced its colocalization with CLD surface and enhanced lipid accumulation. Overexpression of ADRP increased lipid accumulation and the concentration of triacylglycerol in GMEC. In contrast, morphological examination revealed that knockdown of ADRP decreased lipid accumulation even when OA was supplemented. This response was confirmed by the reduction in mass of cellular TG when ADRP was knocked down. The fact that knockdown of ADRP did not completely eliminate lipid accumulation at a morphological level in GMEC without OA suggests that some other compensatory factors may also aid in the process of CLD formation. The ADRP reversed the decrease of CLD accumulation induced by adipose triglyceride lipase. This is highly suggestive of ADRP promoting triacylglycerol stability within CLD by preventing access to adipose triglyceride lipase. Collectively, these data provide direct in vitro evidence that ADRP plays a key role in CLD formation and stability in GMEC. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Biochemical Characterization of Lipases Obtained from Acinetobacter psychrotolerans Strains

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Şule SEREN

2017-12-01

Full Text Available In this study, extracellular lipases obtained from Acinetobacter psychrotolerans strains (Xg1 and Xg2 were characterized. The effects of varying pH values (3.0-10.0 and various temperatures (10-90 °C on lipase activities were examined. Also the effects of different metal ions, organic solvents and detergents on lipases were studied. The extracellular crude lipases were concentrated using ultrafiltration. Zymogram analysis of these lipases was performed. Lipases exhibited maximum activity at pH 8 and 30 °C.  While lipase obtained from the Xg1 strain exhibited the highest stability in the presence of various organic solvents, including hexane, ethyl acetate, chloroform and N,N dietil formamide, lipase obtained from the Xg2 strain was sensitive in the presence of isopropanol, acetonitrile, and butan-1-ol. The lipases of the Xg1 and Xg2 strains were inhibited in the presence of Cu2+ and Zn2+. Also, the lipase of the Xg1 strain was inhibited in the presence of Fe3+. In the presence of EDTA, the lipase activities of the Xg1 and Xg2 strains were partially inhibited. In presence of SDS, they were exactly inhibited. According to the zymogram results, the molecular weights of the lipases obtained from the Acinetobacter psychrotolerans Xg1 and Xg2 strains have been found approximately 37 and 30 kDa, respectively.

Role of Hepatic Lipase and Endothelial Lipase in High-Density Lipoprotein-Mediated Reverse Cholesterol Transport

NARCIS (Netherlands)

Annema, Wijtske; Tietge, Uwe J. F.

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

The role of glucose, insulin and NEFA in regulating tissue triglyceride accumulation: Substrate cooperation in adipose tissue versus substrate competition in skeletal muscle.

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Guzzardi, M A; Hodson, L; Guiducci, L; La Rosa, F; Salvadori, P A; Burchielli, S; Iozzo, P

2017-11-01

Metabolic factors initiating adipose tissue expansion and ectopic triglyceride accumulation are not completely understood. We aimed to investigate the independent role of circulating glucose, NEFA and insulin on glucose and NEFA uptake, and lipogenesis in skeletal muscle and subcutaneous adipose tissue (SCAT). Twenty-two pigs were stratified according to four protocols: 1) and 2) low NEFA + high insulin ± high glucose (hyperinsulinaemia-hyperglycaemia or hyperinsulinaemia-euglycaemia), 3) high NEFA + low insulin (fasting), 4) low NEFA + low insulin (nicotinic acid). Positron emission tomography with [ 18 F]fluoro-2-deoxyglucose and [ 11 C]acetate, was combined with [ 14 C]acetate and [U- 13 C]palmitate enrichment techniques to assess glucose and lipid metabolism. Hyperinsulinaemia increased glucose extraction, whilst hyperglycaemia enhanced glucose uptake in skeletal muscle and SCAT. In SCAT, during hyperglycaemia, elevated glucose uptake was accompanied by greater [U- 13 C]palmitate-TG enrichment compared to the other groups, and by a 39% increase in de novo lipogenesis (DNL) compared to baseline, consistent with a 70% increment in plasma lipogenic index. Conversely, in skeletal muscle, [U- 13 C]palmitate-TG enrichment was higher after prolonged fasting. Our data show the necessary role of hyperglycaemia-hyperinsulinaemia vs euglycaemia-hyperinsulinaemia in promoting expansion of TG stores in SCAT, by the consensual elevation in plasma NEFA and glucose uptake and DNL. In contrast, skeletal muscle NEFA uptake for TG synthesis is primarily driven by circulating NEFA levels. These results suggest that a) prolonged fasting or dietary regimens enhancing lipolysis might promote muscle steatosis, and b) the control of glucose levels, in association with adequate energy balance, might contribute to weight loss. Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and

Maximization of Intracellular Lipase Production in a Lipase-Overproducing Mutant Derivative of Rhizopus oligosporus DGM 31: A Kinetic Study

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Tehreema Iftikhar

2008-01-01

Full Text Available Regulation and maximization of lipase production in a mutant derivative of R. oligosporus has been investigated using different substrates, inoculum sizes, pH of the medium, temperature, and nitrogen sources in shake flask experiments and batch fermentation in a fermentor. The production of intracellular lipase was improved 3 times following medium optimization involving one-at-a-time approach and aeration in the fermentor. Interestingly, intracellular lipase was poorly induced by oils, instead its production was induced by sugars, mainly starch, lactose, sucrose, xylose, glucose and glycerol. Dependent variables studied were cell mass, lipase activity, lipase yield, lipase specific and volumetric rate of formation. It was confirmed that lipase production in the derepressed mutant is sufficiently uncoupled from catabolite repression. The results of average specific productivities at various temperatures worked out according to the Arrhenius equation revealed that mutation decreased the magnitude of enthalpy and entropy demand in the inactivation equilibrium during product formation, suggesting that mutation made the metabolic network of the organism thermally more stable. The highest magnitudes of volumetric productivity (QP=490 IU/(L·h and other product attributes of lipase formation occurring on optimized medium in the fermentor are greater than the values reported by other workers. The purified enzyme is monomeric in nature and exhibits stability up to 80 °C and pH=6.0–8.0. Activation energy, enthalpy and entropy of catalysis at 50 °C, and magnitudes of Gibbs free energy for substrate binding, transition state stabilization and melting point indicated that this lipase is highly thermostable.

The Lp_3561 and Lp_3562 enzymes support a functional divergence process in the lipase/esterase toolkit from Lactobacillus plantarum

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Maria Esteban-Torres

2016-07-01

Full Text Available Lactobacillus plantarum species is a good source of esterases since both lipolytic and esterase activities have been described for strains of this species. No fundamental biochemical difference exists among esterases and lipases since both share a common catalytic mechanism. L. plantarum WCFS1 possesses a protein, Lp_3561, which is 44% identical to a previously described lipase, Lp_3562. In contrast to Lp_3562, Lp_3561 was unable to degrade esters possessing a chain length higher than C4 and the triglyceride tributyrin. As in other L. plantarum esterases, the electrostatic potential surface around the active site in Lp_3561 is predicted to be basic, whereas it is essentially neutral in the Lp_3562 lipase. The fact that the genes encoding both proteins were located contiguously in the L. plantarum WCFS1 genome, suggests that they originated by tandem duplication, and therefore are paralogs as new functions have arisen during evolution. The presence of the contiguous lp_3561 and lp_3562 genes was studied among L. plantarum strains. They are located in a 8,903 bp DNA fragment that encodes proteins involved in the catabolism of sialic acid and are predicted to increase bacterial adaptability under certain growth conditions.

Structural insights into methanol-stable variants of lipase T6 from Geobacillus stearothermophilus.

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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.

Lipase production by recombinant strains of Aspergillus niger expressing a lipase-encoding gene from Thermomyces lanuginosus

DEFF Research Database (Denmark)

Prathumpai, Wai; Flitter, S.J.; Mcintyre, Mhairi

2004-01-01

Two recombinant strains of Aspergillus niger (NW 297-14 and NW297-24) producing a heterologous lipase from Thermomyces lanuginosus were constructed. The heterologous lipase was expressed using the TAKA amylase promoter from Aspergillus oryzae. The production kinetics of the two strains on different...... shows that it is possible to obtain high productivities of heterologous fungal enzymes in A. niger. However, SDS-PAGE analysis showed that most of the produced lipase was bound to the cell wall....

Adiposity and Glycemic Control in Children Exposed to Perfluorinated Compounds

DEFF Research Database (Denmark)

Timmermann, Clara Amalie G.; Rossing, Laura I.; Grontved, Anders

2014-01-01

, waist circumference, leptin, adiponectin, insulin, glucose, and triglyceride concentrations were assessed in 8- to 10-year-old children in 1997 in a subset of the European Youth Heart Study, Danish component. Plasma PFC concentrations were available from 499 children. Linear regression models were......Objective: Our objective was to explore whether childhood exposure to perfluorinated and polyfluorinated compounds (PFCs), widely used stain- and grease-repellent chemicals, is associated with adiposity and markers of glycemic control. Materials and Methods: Body mass index, skinfold thickness...... perfluorooctane sulfonic acid/mL plasma was associated with 16.2% (95% confidence interval [CI], 5.2%-28.3%) higher insulin concentration, 12.0% (95% CI, 2.4%-22.4%) higher β-cell activity, 17.6% (95% CI, 5.8%-30.8%) higher insulin resistance, and 8.6% (95% CI, 1.2%-16.5%) higher triglyceride concentrations...

Lipoprotein lipase activity and mass, apolipoprotein C-II mass and polymorphisms of apolipoproteins E and A5 in subjects with prior acute hypertriglyceridaemic pancreatitis

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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.

Lipoprotein lipase activity and mass, apolipoprotein C-II mass and polymorphisms of apolipoproteins E and A5 in subjects with prior acute hypertriglyceridaemic pancreatitis

Science.gov (United States)

2009-01-01

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. PMID:19534808

Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae

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Seniwati Dali

2011-01-01

Full Text Available 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 temperature, thermal stability and reusability were carried out. The results showed that free lipase had optimum pH 8,2 and optimum temperature 35 °C while the immobilized lipase had optimum 8,2 and optimum temperature 45 °C. The thermal stability of the immobilized lipase, relative to that of the free lipase, was markedly increased. The immobilized lipase can be reused for at least six times.

Adiposity measurements in association with metabolic syndrome in older men have different clinical implications.

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Hsu, Chun-Hsien; Lin, Jiunn-Diann; Hsieh, Chang-Hsun; Lau, Shu Chuen; Chiang, Wei-Yong; Chen, Yen-Lin; Pei, Dee; Chang, Jin-Biou

2014-03-01

Obesity is a major public health problem, and measuring adiposity accurately and predicting its future comorbidities are important issues. Therefore, we hypothesized that 4 adiposity measurements, body mass index (BMI), waist circumference (WC), waist-to-height ratio, and body fat percentage, have different physiological meanings and distinct associations with adverse health consequences. This study aimed to investigate the relationship of these 4 measurements with metabolic syndrome (MetS) components and identify the most associated factor for MetS occurrence in older, non-medicated men. Cross-sectional data from 3004 men, all 65 years of age and older, were analyzed. The correlation and association between adiposity measurements and MetS components were evaluated by Pearson correlation and multiple linear regression. Based on multivariate logistic regression, BMI and WC were significantly associated with MetS and were selected to build a combined model of receiver operating characteristic curves to increase the diagnosis accuracy for MetS. The results show that BMI is independently associated with systolic and diastolic blood pressure; WC and body fat percentage are associated with fasting plasma glucose and log transformation of triglyceride; BMI and WC are negatively associated with high-density lipoprotein cholesterol (HDL-C); and WC is a better discriminate for MetS than BMI, although the combined model (WC + BMI) is not significantly better than WC alone. Based on these results, we conclude that the 4 adiposity measurements have different clinical implications. Thus, in older men, BMI is an important determinant for blood pressure and HDL-C. Waist circumference is associated with the risk of fasting plasma glucose, HDL-C, triglyceride, and MetS occurrence. The combined model did not increase the diagnosis accuracy. Copyright © 2014 Elsevier Inc. All rights reserved.

Nutritional status induces divergent variations of GLUT4 protein content, but not lipoprotein lipase activity, between adipose tissues and muscles in adult cattle.

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Bonnet, Muriel; Faulconnier, Yannick; Hocquette, Jean-François; Bocquier, François; Leroux, Christine; Martin, Patrice; Chilliard, Yves

2004-10-01

Metabolic adaptations to variations in food supply are incompletely understood in ruminant animal adipose tissue (AT) and muscle. To explore this, we studied lipid metabolism and glucose transport potential in one internal and one external AT, as well as in one oxidative and one glycolytic muscle from control, 7 d underfed and 21 d refed adult cows. Refeeding increased (+79 to +307 %) the activities of enzymes involved in de novo lipogenesis (fatty acid synthase, malic enzyme, glucose-6-phosphate dehydrogenase) in perirenal and subcutaneous AT; underfeeding did not modify these variables. Underfeeding decreased the activities of lipoprotein lipase (LPL) in perirenal AT (-70 %) and cardiac muscle (-67 %), but did not modify the activities in subcutaneous AT and longissimus thoracis. Refeeding increased LPL activities in all tissues (+40 to +553 %) to levels comparable with (cardiac muscle) or greater than (AT, longissimus thoracis) those observed in control cows. Such variations in perirenal and cardiac muscle LPL activities did not result from variations in LPL mRNA levels, but suggest a post-transcriptional regulation of LPL in these nutritional conditions. Underfeeding did not modify GLUT4 contents in perirenal AT and muscles, while refeeding increased it only in perirenal AT (+250 %). Our present results contrast with previous results in rats, where LPL is regulated in opposite directions in AT and muscles, and GLUT4 is generally increased by fasting and decreased by refeeding in skeletal muscles. The present results highlight the bovine specificity of the response, which probably arises in part from peculiarities of ruminant animals for nutrient digestion and absorption.

Triglyceride level

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... page: //medlineplus.gov/ency/article/003493.htm Triglyceride level To use the sharing features on this page, please enable JavaScript. The triglyceride level is a blood test to measure the amount ...

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

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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.

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

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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.

A novel PNPLA2 mutation causes neutral lipid storage disease with myopathy (NLSDM) presenting muscular dystrophic features with lipid storage and rimmed vacuoles.

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Chen, J; Hong, D; Wang, Z; Yuan, Y

2010-01-01

Neutral lipid storage disease with myopathy (NLSDM) is a type of lipid storage myopathy arising due to a mutation in the PNPLA2 gene encoding an adipose triglyceride lipase responsible for the degradation of intracellular triglycerides. Herein, we report the cases of two siblings manifesting slowly progressive proximal and distal limb weakness in adulthood. One of the patients had dilated cardiomyopathy, hearing loss and short stature. Muscle specimens of the 2 patients revealed muscular dystrophic features with massive lipid droplets and numerous rimmed vacuoles in the fibers. A novel homozygous mutation IVS2+1G > A in the PNPLA2 gene was identified in the 2 cases, but not in the healthy familial individuals. The presence of massive lipid droplets with muscular dystrophic changes and rimmed vacuoles in muscle fibers might be one of the characteristic pathological changes of NLSDM.

Lipase immobilization and production of fatty acid methyl esters from canola oil using immobilized lipase

International Nuclear Information System (INIS)

Yuecel, Yasin; Demir, Cevdet; Dizge, Nadir; Keskinler, Buelent

2011-01-01

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 o C 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%.

The Signal Transducer and Activator of Transcription 1 (STAT1 Inhibits Mitochondrial Biogenesis in Liver and Fatty Acid Oxidation in Adipocytes.

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Jennifer D Sisler

Full Text Available The transcription factor STAT1 plays a central role in orchestrating responses to various pathogens by activating the transcription of nuclear-encoded genes that mediate the antiviral, the antigrowth, and immune surveillance effects of interferons and other cytokines. In addition to regulating gene expression, we report that STAT1-/- mice display increased energy expenditure and paradoxically decreased release of triglycerides from white adipose tissue (WAT. Liver mitochondria from STAT1-/- mice show both defects in coupling of the electron transport chain (ETC and increased numbers of mitochondria. Consistent with elevated numbers of mitochondria, STAT1-/- mice expressed increased amounts of PGC1α, a master regulator of mitochondrial biogenesis. STAT1 binds to the PGC1α promoter in fed mice but not in fasted animals, suggesting that STAT1 inhibited transcription of PGC1α. Since STAT1-/- mice utilized more lipids we examined white adipose tissue (WAT stores. Contrary to expectations, fasted STAT1-/- mice did not lose lipid from WAT. β-adrenergic stimulation of glycerol release from isolated STAT1-/- WAT was decreased, while activation of hormone sensitive lipase was not changed. These findings suggest that STAT1-/- adipose tissue does not release glycerol and that free fatty acids (FFA re-esterify back to triglycerides, thus maintaining fat mass in fasted STAT1-/- mice.

Synthesis of medium-chain length capsinoids from coconut oil catalyzed by Candida rugosa lipases.

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Trbojević Ivić, Jovana; Milosavić, Nenad; Dimitrijević, Aleksandra; Gavrović Jankulović, Marija; Bezbradica, Dejan; Kolarski, Dušan; Veličković, Dušan

2017-03-01

A commercial preparation of Candida rugosa lipases (CRL) was tested for the production of capsinoids by esterification of vanillyl alcohol (VA) with free fatty acids (FA) and coconut oil (CO) as acyl donors. Screening of FA chain length indicated that C8-C12 FA (the most common FA found in CO triglycerides) are the best acyl-donors, yielding 80-85% of their specific capsinoids. Hence, when CO, which is rich in these FA, was used as the substrate, a mixture of capsinoids (vanillyl caprylate, vanillyl decanoate and vanillyl laurate) was obtained. The findings presented here suggest that our experimental method can be applied for the enrichment of CO with capsinoids, thus giving it additional health promoting properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mechanism of acetaldehyde-induced deactivation of microbial lipases

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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

Enhanced Inflammation without Impairment of Insulin Signaling in the Visceral Adipose Tissue of 5α-Dihydrotestosterone-Induced Animal Model of Polycystic Ovary Syndrome.

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Milutinović, Danijela Vojnović; Nikolić, Marina; Veličković, Nataša; Djordjevic, Ana; Bursać, Biljana; Nestorov, Jelena; Teofilović, Ana; Antić, Ivana Božić; Macut, Jelica Bjekić; Zidane, Abdulbaset Shirif; Matić, Gordana; Macut, Djuro

2017-09-01

Polycystic ovary syndrome is a heterogeneous endocrine and metabolic disorder associated with abdominal obesity, dyslipidemia and insulin resistance. Since abdominal obesity is characterized by low-grade inflammation, the aim of the study was to investigate whether visceral adipose tissue inflammation linked to abdominal obesity and dyslipidemia could lead to impaired insulin sensitivity in the animal model of polycystic ovary syndrome.Female Wistar rats were treated with nonaromatizable 5α-dihydrotestosterone pellets in order to induce reproductive and metabolic characteristics of polycystic ovary syndrome. Glucose, triglycerides, non-esterified fatty acids and insulin were determined in blood plasma. Visceral adipose tissue inflammation was evaluated by the nuclear factor kappa B intracellular distribution, macrophage migration inhibitory factor protein level, as well as TNFα, IL6 and IL1β mRNA levels. Insulin sensitivity was assessed by intraperitoneal glucose tolerance test and homeostasis model assessment index, and through analysis of insulin signaling pathway in the visceral adipose tissue.Dihydrotestosterone treatment led to increased body weight, abdominal obesity and elevated triglycerides and non-esterified fatty acids, which were accompanied by the activation of nuclear factor kappa B and increase in macrophage migration inhibitory factor, IL6 and IL1β levels in the visceral adipose tissue. In parallel, insulin sensitivity was affected in 5α-dihydrotestosterone-treated animals only at the systemic and not at the level of visceral adipose tissue.The results showed that abdominal obesity and dyslipidemia in the animal model of polycystic ovary syndrome were accompanied with low-grade inflammation in the visceral adipose tissue. However, these metabolic disturbances did not result in decreased tissue insulin sensitivity. © Georg Thieme Verlag KG Stuttgart · New York.

Biodegradable products by lipase biocatalysis.

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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.

Lipase entrapment in PVA/Chitosan biodegradable film for reactor coatings

Energy Technology Data Exchange (ETDEWEB)

Batista, Karla A. [Departamento de Bioquímica e Biologia Molecular, Laboratório de Química de Proteínas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970, Goiânia, GO (Brazil); Lopes, Flavio Marques [Departamento de Bioquímica e Biologia Molecular, Laboratório de Química de Proteínas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970, Goiânia, GO (Brazil); Unidade Universitária de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Anápolis, GO (Brazil); Yamashita, Fabio [Departamento de Tecnologia de Alimentos e Medicamentos, Laboratório de Tecnologia, Universidade Estadual de Londrina, Cx. Postal 6001, CEP 86051-990, Londrina, PR (Brazil); Fernandes, Kátia Flávia, E-mail: katia@icb.ufg.br [Departamento de Bioquímica e Biologia Molecular, Laboratório de Química de Proteínas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970, Goiânia, GO (Brazil)

2013-04-01

This study reports the development and characterization of novel biodegradable film, based on chitosan and polyvinyl alcohol containing lipase entrapped. The films showed a thickness of 70.4 and 79 μm to PVA/Chitosan and PVA/Chitosan/Lipase, respectively. The entrapment of lipase in PVA/Chitosan film resulted in increasing of 69.4% tensile strength (TS), and 52.4% of elongation. SEM images showed the formation of a continuous film, without pores or cracks. The lipase entrapment efficiency was estimated in 92% and the films were repeatedly used for 25 hydrolytic cycles, maintaining 62% of initial activity. The PVA/Chitosan/Lipase film was used for olive oil hydrolysis of high performance. These results indicate that PVA/Chitosan/Lipase is a promising material for biotechnology applications such as triacylglycerol hydrolysis and biodiesel production. - Highlights: ► Development and characterization of PVA/Chitosan biodegradable film ► Lipase immobilization onto PVA/Chitosan film ► PVA/Chitosan/Lipase film for reactor coating ► Olive oil hydrolysis using PVA/Chitosan/Lipase film.

Lipase entrapment in PVA/Chitosan biodegradable film for reactor coatings

International Nuclear Information System (INIS)

Batista, Karla A.; Lopes, Flavio Marques; Yamashita, Fabio; Fernandes, Kátia Flávia

2013-01-01

This study reports the development and characterization of novel biodegradable film, based on chitosan and polyvinyl alcohol containing lipase entrapped. The films showed a thickness of 70.4 and 79 μm to PVA/Chitosan and PVA/Chitosan/Lipase, respectively. The entrapment of lipase in PVA/Chitosan film resulted in increasing of 69.4% tensile strength (TS), and 52.4% of elongation. SEM images showed the formation of a continuous film, without pores or cracks. The lipase entrapment efficiency was estimated in 92% and the films were repeatedly used for 25 hydrolytic cycles, maintaining 62% of initial activity. The PVA/Chitosan/Lipase film was used for olive oil hydrolysis of high performance. These results indicate that PVA/Chitosan/Lipase is a promising material for biotechnology applications such as triacylglycerol hydrolysis and biodiesel production. - Highlights: ► Development and characterization of PVA/Chitosan biodegradable film ► Lipase immobilization onto PVA/Chitosan film ► PVA/Chitosan/Lipase film for reactor coating ► Olive oil hydrolysis using PVA/Chitosan/Lipase film

Requirement of lid2 for interfacial activation of a family I.3 lipase with unique two lid structures.

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Cheng, Maria; Angkawidjaja, Clement; Koga, Yuichi; Kanaya, Shigenori

2012-10-01

A family I.3 lipase from Pseudomonas sp. MIS38 (PML) is characterized by the presence of two lids (lid1 and lid2) that greatly change conformation upon substrate binding. While lid1 represents the commonly known lid in lipases, lid2 is unique to PML and other family I.3 lipases. To clarify the role of lid2 in PML, a lid2 deletion mutant (ΔL2-PML) was constructed by deleting residues 35-64 of PML. ΔL2-PML requires calcium ions for both lipase and esterase activities as does PML, suggesting that it exhibits activity only when lid1 is fully open and anchored by the catalytically essential calcium ion, as does PML. However, when the enzymatic activity was determined using triacetin, the activity of PML exponentially increased as the substrate concentration reached and increased beyond the critical micellar concentration, while that of ΔL2-PML did not. These results indicate that PML undergoes interfacial activation, while ΔL2-PML does not. The activities of ΔL2-PML for long-chain triglycerides significantly decreased while its activity for fatty acid ethyl esters increased, compared with those of PML. Comparison of the tertiary models of ΔL2-PML in a closed and open conformation, which are optimized by molecular dynamics simulation, with the crystal structures of PML suggests that the hydrophobic surface area provided by lid1 and lid2 in an open conformation is considerably decreased by the deletion of lid2. We propose that the hydrophobic surface area provided by these lids is necessary to hold the micellar substrates firmly to the active site and therefore lid2 is required for interfacial activation of PML. © 2012 The Authors Journal compilation © 2012 FEBS.

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

Detection of triglyceride using an iridium nano-particle catalyst based amperometric biosensor.

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Liao, Wei-Yin; Liu, Chung-Chiun; Chou, Tse-Chuan

2008-12-01

The detection and quantification of triglyceride (TG) using an iridium nano-particle modified carbon based biosensor was successfully carried out in this study. The detection procedures were based on the electrochemical detection of enzymatically produced NADH. TG was hydrolyzed by lipase and the glycerol produced was catalytically oxidized by NAD-dependent glycerol dehydrogenase producing NADH in a solution containing NAD(+). Glyceryl tributyrate, a short chain triglyceride, was chosen as the substrate for the evaluation of this TG biosensor in bovine serum and human serum. A linear response to glyceryl tributyrate in the concentration range of 0 to 10 mM and a sensitivity of 7.5 nA mM(-1) in bovine serum and 7.0 nA mM(-1) in human serum were observed experimentally. The potential interference of species such as uric acid (UA) and ascorbic acid (AA) was assessed. The incorporation of a selected surfactant and an increase in the incubation temperature appeared to enhance the performance of this biosensor. The conditions for the determination of TG levels in bovine serum using this biosensor were optimized, with sunflower seed oil being used as an analyte to simulate the detection of TG in blood. The experimental results demonstrated that this iridium nano-particle modified working electrode based biosensor provided a relatively simple means for the accurate determination of TG in serum.

Triglycerides and cardiovascular disease

DEFF Research Database (Denmark)

Nordestgaard, Børge G; Varbo, Anette

2014-01-01

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...... of acute pancreatitis and possibly cardiovascular disease. Although randomised trials showing cardiovascular benefit of triglyceride reduction are scarce, new triglyceride-lowering drugs are being developed, and large-scale trials have been initiated that will hopefully provide conclusive evidence...

Regulation of lipoprotein lipase in primary cultures of isolated human adipocytes

International Nuclear Information System (INIS)

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 125 I-insulin binding. In addition, chloroquine induced an increase in cell-associated 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

Associations Between Adiposity and Metabolic Syndrome Over Time: The Healthy Twin Study.

Science.gov (United States)

Song, Yun-Mi; Sung, Joohon; Lee, Kayoung

2017-04-01

We evaluated the association between changes in adiposity traits including anthropometric and fat mass indicators and changes in metabolic syndrome traits including metabolic syndrome clustering and individual components over time. We also assessed the shared genetic and environmental correlations between the two traits. Participants were 284 South Korean twin individuals and 279 nontwin family members had complete data for changes in adiposity traits and metabolic syndrome traits of the Healthy Twin study. Mixed linear model and bivariate variance-component analysis were applied. Over a period of 3.1 ± 0.6 years of study, changes in adiposity traits [body mass index (BMI), waist circumference, total fat mass, and fat mass to lean mass ratio] had significant associations with changes in metabolic syndrome clustering [high blood pressure, high serum glucose, high triglycerides (TG), and low high-density lipoprotein cholesterol] after adjusting for intra-familial and sibling correlations, age, sex, baseline metabolic syndrome clustering, and socioeconomic factors and health behaviors at follow-up. Change in BMI associated significantly with changes in individual metabolic syndrome components compared to other adiposity traits. Change in metabolic syndrome component TG was a better predictor of changes in adiposity traits compared to changes in other metabolic components. These associations were explained by significant environmental correlations but not by genetic correlations. Changes in anthropometric and fat mass indicators were positively associated with changes in metabolic syndrome clustering and those associations appeared to be regulated by environmental influences.

Catalytic Properties of Lipase Extracts from Aspergillus niger

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Cintia M. Romero

2006-01-01

Full Text Available Screening of lipolytic strains using Rhodamine-B/olive oil plate technique allowed the selection of Aspergillus niger MYA 135. Lipase production in submerged culture containing 2 % olive oil was enhanced by more than 50 % compared to basal cultural conditions. Optimal catalytic conditions for olive oil-induced lipase were pH=6.5 and 30–35 °C. These values were shifted to the acid region (4.0–6.5 and 35–37 °C when lipase extract was produced under basal conditions. Slight changes of the residual lipase activity against the pH were found. However, preincubation at either 37 or 40 °C caused an increase in the olive oil-inducible lipolytic activity. On the contrary, lipase residual activity decreases in the 30–55 °C range when it was produced in basal medium. Lipolytic extracts were almost not deactivated in presence of 50 % water-miscible organic solvents. However, water-immiscible aliphatic solvents reduced the lipase activity between 20 and 80 %.

Isolation and analysis of lipase-overproducing mutants of Serratia marcescens.

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Kawai, E; Akatsuka, H; Sakurai, N; Idei, A; Matsumae, H; Shibatani, T; Komatsubara, S; Omori, K

2001-01-01

We have isolated a lipase-overproducing mutant, GE14, from Serratia marcescens 8000 after three rounds of N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis. The mutant GE14 produced 95 kU/ml of extracellular lipase in the lipase medium, which was about threefold higher than that of produced by the original strain 8000. Enzymatic characteristics including specific activity of purified lipases from culture supernatants of GE14 and 8000 were almost same. The lipase gene (lipA) of GE14 contained two base substitutions; one in the promoter region and another in the N-terminal region of the lipA gene without an amino acid substitution. Promoter analysis using lipA-lacZ fusion plasmids revealed that these substitutions were responsible for the increase in the lipA expression level, independently. In contrast, no base substitution was found in the genes encoding the lipase secretion device, the Lip system. In addition, the genes coding for metalloprotease and the cell surface layer protein which are both secreted through the Lip system and associated with extracellular lipase production, also contained no base substitution. The strain GE14 carrying a high-copy-number lipA plasmid produced a larger amount of the extracellular lipase than the recombinant strains of 8000 and other mutants also did, indicating that GE14 was not only a lipase-overproducing strain, but also an advantageous host strain for overproducing the lipase by a recombinant DNA technique. These results suggest that the lipase-overproducing mutant GE14 and its recombinant strains are promising candidates for the industrial production of the S. marcescens lipase.

The role of adiposity in cardiometabolic traits: a Mendelian randomization analysis.

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Tove Fall

Full Text Available The association between adiposity and cardiometabolic traits is well known from epidemiological studies. Whilst the causal relationship is clear for some of these traits, for others it is not. We aimed to determine whether adiposity is causally related to various cardiometabolic traits using the Mendelian randomization approach.We used the adiposity-associated variant rs9939609 at the FTO locus as an instrumental variable (IV for body mass index (BMI in a Mendelian randomization design. Thirty-six population-based studies of individuals of European descent contributed to the analyses. Age- and sex-adjusted regression models were fitted to test for association between (i rs9939609 and BMI (n  =  198,502, (ii rs9939609 and 24 traits, and (iii BMI and 24 traits. The causal effect of BMI on the outcome measures was quantified by IV estimators. The estimators were compared to the BMI-trait associations derived from the same individuals. In the IV analysis, we demonstrated novel evidence for a causal relationship between adiposity and incident heart failure (hazard ratio, 1.19 per BMI-unit increase; 95% CI, 1.03-1.39 and replicated earlier reports of a causal association with type 2 diabetes, metabolic syndrome, dyslipidemia, and hypertension (odds ratio for IV estimator, 1.1-1.4; all p < 0.05. For quantitative traits, our results provide novel evidence for a causal effect of adiposity on the liver enzymes alanine aminotransferase and gamma-glutamyl transferase and confirm previous reports of a causal effect of adiposity on systolic and diastolic blood pressure, fasting insulin, 2-h post-load glucose from the oral glucose tolerance test, C-reactive protein, triglycerides, and high-density lipoprotein cholesterol levels (all p < 0.05. The estimated causal effects were in agreement with traditional observational measures in all instances except for type 2 diabetes, where the causal estimate was larger than the observational estimate (p  =  0

Stability of immobilized candida sp. 99-125 Lipase for biodiesel production

Energy Technology Data Exchange (ETDEWEB)

Lu, J. [Beijing Bioprocess Key Laboratory, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing (China); Bioengineering Department, Zhengzhou University, Zhengzhou (China); Deng, L.; Nie, K.; Wang, F.; Tan, T. [Beijing Bioprocess Key Laboratory, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing (China)

2012-12-15

The stability of the immobilized lipase from Candida sp. 99-125 during biodiesel production was investigated. The lipase was separately incubated in the presence of various reaction components such as soybean oil, oleic acid methyl ester, n-hexane, water, methanol, and glycerol, or the lipase was stored at 60, 80, 100 and 120 C. Thereafter the residual lipase activity was determined by methanolysis reaction. The results showed that the lipase was rather stable in the reaction media, except for methanol and glycerol. The stability study performed in a reciprocal shaker indicated that enzyme desorption from the immobilized lipase mainly contributed to the lipase inactivation in the water system. So the methanol and glycerol contents should be controlled more precisely to avoid lipase inactivation, and the immobilization method should be improved with regard to lipase desorption. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

PEDIATRIC VISCERAL ADIPOSITY INDEX ADAPTATION CORRELATES WITH HOMA-IR, MATSUDA, AND TRANSAMINASES.

Science.gov (United States)

Hernández, María José Garcés; Klünder, Miguel; Nieto, Nayely Garibay; Alvarenga, Juan Carlos López; Gil, Jenny Vilchis; Huerta, Samuel Flores; Siccha, Rosa Quispe; Hernandez, Joselin

2018-03-01

Visceral adiposity index (VAI) is a mathematical model associated with cardiometabolic risk in adults, but studies on children failed to support this association. Our group has proposed a pediatric VAI model using pediatric ranges, but it has not yet been evaluated and needs further adjustments. The objective of this study was to further adjust the proposed pediatric VAI by age, creating a new pediatric metabolic index (PMI), and assess the correlation of the PMI with insulin resistance indexes and hepatic enzymes. A cross-sectional design with data from 396 children (age 5 to 17 years) was analyzed with a generalized linear model to find the coefficients for triglycerides, high-density-lipoprotein cholesterol, and waist circumference-body mass index quotient. The model was constructed according to sex and age and designated PMI. A cross-validation analysis was performed and a receiver operating characteristic curve was used to determine cut-off points. Significant moderate correlation was found between PMI and homeostatic model assessment of insulin resistance (HOMA-IR) ( r = 0.452; P = .003), Matsuda ( r = -0.366; P = .019), alanine aminotransferase ( r = 0.315, P = .045), and γ-glutamyltransferase ( r = 0.397; P = .010). A PMI score >1.7 was considered as risk. PMI correlates with HOMA-IR, Matsuda, and hepatic enzymes. It could be helpful for identifying children at risk for cardiometabolic diseases. ALT = alanine transaminase BMI = body mass index GGT = γ-glutamyltransferase HDL-C = high-density-lipoprotein cholesterol HOMA-IR = homeostatic model assessment of insulin resistance hs-CRP = high sensitivity C-reactive protein ISI = insulin sensitivity index NAFLD = nonalcoholic fatty liver disease PMI = pediatric metabolic index QUICKI = quantitative insulin sensitivity check index ROC = receiver operating characteristic TG = triglyceride TNF-α = tumor necrosis factor-alpha VAI = visceral adiposity index VAT = visceral adipose tissue WC = waist circumference.

Enantioselectivity and Thermostability of a Novel Hyperhermotolerant Lipase from Geobacillus Thermodenitrificans nr68 (Lip.nr-68) on Secondary Racemic Alcohols Acetylation

Science.gov (United States)

Nik Him, N. R.; Ibrahim, D.

2018-05-01

In our previous work, a new lipase enzyme has been purified from a species identified as a Gram negative Geobacillus thermodenitrificans nr68, isolated from a hot spring in Malaysia with growth temperature of 48°C. This new lipase, called Lip.nr-68 has been characterized as a hyperthermotolerant protein with high stability at 65°C and has been showing excellent characteristics that are very much comparable yet better than some of those of well-known industrially-used lipases. It shows high activity against long-chain triglycerides with molecular weight of the purified enzyme estimated to be 33.5 kDa using SDS-PAGE analysis. This paper is focusing on hyperthermotolerant Lip.nr-68 performance in promoting for enantioselectivity activities towards three secondary racemic alcohols namely 1-phenylethanol, 1-cyclohexilethanol and 1-(naft-2-il) ethanol by acetylation with vinyl acetate. Lip.nr-68 has been confirmed to show high and usual enantioselectivitiy according to the Kazlauskas Rule towards all secondary racemic alcohols and has significantly approved as an enantiomer selective biocatalyst towards 1-phenylethanol and 1-cyclohexylethanol at 65°C. Lip.nr-68 has showed a reduction of (R) and (S) enantiomers as well as the production of 68-98% ee and almost 94% yield of 3-4 mg/ml for 1-cyclohexilethanol.

Waist Circumference, Body Mass Index, and Other Measures of Adiposity in Predicting Cardiovascular Disease Risk Factors among Peruvian Adults.

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Knowles, K M; Paiva, L L; Sanchez, S E; Revilla, L; Lopez, T; Yasuda, M B; Yanez, N D; Gelaye, B; Williams, M A

2011-01-24

Objectives. To examine the extent to which measures of adiposity can be used to predict selected components of metabolic syndrome (MetS) and elevated C-reactive protein (CRP). Methods. A total of 1,518 Peruvian adults were included in this study. Waist circumference (WC), body mass index (BMI), waist-hip ratio (WHR), waist-height ratio (WHtR), and visceral adiposity index (VAI) were examined. The prevalence of each MetS component was determined according to tertiles of each anthropometric measure. ROC curves were used to evaluate the extent to which measures of adiposity can predict cardiovascular risk. Results. All measures of adiposity had the strongest correlation with triglyceride concentrations (TG). For both genders, as adiposity increased, the prevalence of Mets components increased. Compared to individuals with low-BMI and low-WC, men and women with high-BMI and high- WC had higher odds of elevated fasting glucose, blood pressure, TG, and reduced HDL, while only men in this category had higher odds of elevated CRP. Overall, the ROCs showed VAI, WC, and WHtR to be the best predictors for individual MetS components. Conclusions. The results of our study showed that measures of adiposity are correlated with cardiovascular risk although no single adiposity measure was identified as the best predictor for MetS.

Lipid accumulation product and triglycerides/glucose index are useful predictors of insulin resistance.

Science.gov (United States)

Mazidi, Mohsen; Kengne, Andre-Pascal; Katsiki, Niki; Mikhailidis, Dimitri P; Banach, Maciej

2018-03-01

To investigate the association of triglycerides/glucose index (TyG index), anthropometrically predicted visceral adipose tissue (apVAT), lipid accumulation product (LAP), visceral adiposity index (VAI) and triglycerides (TG):high density lipoprotein-cholesterol (HDL-C) ratio with insulin resistance (IR) in adult Americans. This study was based on data from three NHANES cycles (2005 to 2010). The TyG index was calculated as ln [TG×fasting glucose/2]. VAI was calculated using gender-specific formulas: men [waist circumference (WC)/39.68+(1.88×body mass index (BMI)]×(TG/1.03)×(1.31/HDL-C); women: [WC/36.58+(1.89×BMI)]×(TG/0.81)×(1.52/HDL-C). LAP index was calculated as [WC-65]×[TG] in men, and [WC-58]×[TG] in women. Correlation and regression analyses accounted for the complex sampling of database. A total of 18,318 subjects was included in this analysis [mean age 47.6Years]; 48.7% (n=8918) men]. The homeostatic model assessment of insulin resistance (HOMA-IR) had a significant positive correlation with the TyG index (r=0.502), LAP (r=0.551), apVAT (r=0.454), TG:HDL-C ratio (r=0.441) and VAI (r=451) (pindex is a simple, cheap and accurate although not perfect, surrogate marker of HOMA-diagnosed IR among adult Americans. Moreover, it has higher predictability than other screening tools which traditionally applied. Among the markers, apVAT had the highest specificity and the TG:HDL-C ratio had the highest sensitivity. Copyright © 2017 Elsevier Inc. All rights reserved.

Molecular characterization of a proteolysis-resistant lipase from Bacillus pumilus SG2

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R. Sangeetha

2014-06-01

Full Text Available 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 lip gene consisted of 650 bp. The experimental molecular weight of SG2 lipase was nearly double that of its theoretical molecular weight, thus suggesting the existence of the functional lipase as a covalent dimer. The proteolytic cleavage sites of the lipase would have been made inaccessible by dimerisation, thus rendering the lipase resistant to protease.

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...

Altering the activation mechanism in Thermomyces lanuginosus lipase

DEFF Research Database (Denmark)

Skjold-Jørgensen, Jakob; Vind, Jesper; Svendsen, Allan

2014-01-01

It is shown by rational site-directed mutagenesis of the lid region in Thermomyces lanuginosus lipase that it is possible to generate lipase variants with attractive features, e.g., high lipase activity, fast activation at the lipid interface, ability to act on water-soluble substrates......, and enhanced calcium independence. The rational design was based on the lid residue composition in Aspergillus niger ferulic acid esterase (FAEA). Five constructs included lipase variants containing the full FAEA lid, a FAEA-like lid, an intermediate lid of FAEA and TlL character, and the entire lid region...... from Aspergillus terreus lipase (AtL). To investigate an altered activation mechanism for each variant compared to that of TlL, a combination of activity- and spectroscopic-based measurements were applied. The engineered variant with a lid from AtL displayed interfacial activation comparable...

Butyl acetate synthesis using immobilized lipase in calcium alginate beads

International Nuclear Information System (INIS)

Mohd Zulkhairi Abdul Rahim; Lee, Pat M.; Lee, Kong H.

2008-01-01

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)

ANGPTL4 variants E40K and T266M are associated with lower fasting triglyceride levels in Non-Hispanic White Americans from the Look AHEAD Clinical Trial

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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.

Adiposity indicators lipid accumulation product and triglyceride-glucose index as alternate criteria for the diagnosis of metabolic obesity in adult

OpenAIRE

Mariya Tabassum; Md. Matiur Rahman; Miliva Mozaffor

2018-01-01

Metabolic obesity refers to the state of having metabolic syndrome irrespective of one’s BMI. This study was aimed to elucidate the lipid accumulation product and triglyceride-glucose index as simple and alternate criteria for the detecting metabolic obesity in adult. The study was conducted in 200 adult (age range: 19-45 years). According to lipid accumulation product and Triglyceride-glucose index, the prevalence of metabolic obesity was 54.0% and 53.5% respectively. With a cutoff value of ...

Gastric lipase: localization of the enzyme in the stomach

International Nuclear Information System (INIS)

DeNigris, S.J.; Hamosh, M.; Hamosh, P.; Kasbekar, D.K.

1986-01-01

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 3 H-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

Differential effect of combined lipase deficiency (cld/cld) on human hepatic lipase and lipoprotein lipase secretion.

Science.gov (United States)

Boedeker, J C; Doolittle, M H; White, A L

2001-11-01

Combined lipase deficiency (cld) is a recessively inherited disorder in mice associated with a deficiency of LPL and hepatic lipase (HL) activity. LPL is synthesized in cld tissues but is retained in the endoplasmic reticulum (ER), whereas mouse HL (mHL) is secreted but inactive. In this study we investigated the effect of cld on the secretion of human HL (hHL) protein mass and activity. Differentiated liver cell lines were derived from cld mice and their normal heterozygous (het) littermates by transformation of hepatocytes with SV40 large T antigen. After transient transfection with lipase expression constructs, secretion of hLPL activity from cld cells was only 12% of that from het cells. In contrast, the rate of secretion of hHL activity and protein mass per unit of expressed hHL mRNA was identical for the two cell lines. An intermediate effect was observed for mHL, with a 46% reduction in secretion of activity from cld cells. The ER glucosidase inhibitor, castanospermine, decreased secretion of both hLPL and hHL from het cells by approximately 70%, but by only approximately 45% from cld cells. This is consistent with data suggesting that cld may result from a reduced concentration of the ER chaperone calnexin. In conclusion, our results demonstrate a differential effect of cld on hLPL, mHL, and hHL secretion, suggesting differential requirements for activation and exit of the enzymes from the ER.

Lipase in milk, curd and cheese

NARCIS (Netherlands)

Geurts, T.J.; Lettink, F.J.; Wouters, J.T.M.

2003-01-01

Presence of lipase in milk, curd, whey and cheese was studied. A small amount of the product was added to a large volume of lipase-free whole milk that had been made sensitive to lipolysis by homogenization. Increase of the acidity of the fat in the mixture, determined after incubation, was

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

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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

Dietary Lipid Sources Influence Fatty Acid Composition in Tissue of Large Yellow Croaker (Larmichthys crocea by Regulating Triacylglycerol Synthesis and Catabolism at the Transcriptional Level.

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Hong Qiu

Full Text Available An 8-week feeding trial was conducted to evaluate the effects of dietary lipid sources on growth performance, fatty acid composition, rate-limiting enzyme activities and gene expression related to lipid metabolism in large yellow croaker (Larmichthys crocea. Five iso-nitrogenous and iso-lipidic experimental diets were formulated to contain different lipid sources, such as fish oil (FO, soybean oil (SO, linseed oil (LO, rapeseed oil (RO and peanut oil (PO, respectively. Triplicate groups of 50 fish (initial weight 13.77±0.07g were stocked in 15 floating net cages (1.5m×1.5m×2.0m. Fish fed the diets containing RO and LO had lower weight gain and specific growth rates than those fed the FO, SO and PO diets. Survival, feed efficiency, protein efficiency ratio, hepatosomatic index, viscerasomatic index and condition factor were not significantly affected by different dietary lipid sources. Fish fed the diet containing FO had higher lipid content in whole body compared with the other groups, whereas fish fed the SO diet had the lowest muscle lipid content. Fatty acid profiles of muscle and liver reflected the fatty acid composition of the diets. Plasma glucose, triglyceride, and the enzymatic activity of aspartate aminotransferase and alanine aminotransferase were significantly influenced by different dietary lipid sources, while total protein, cholesterol, superoxide dismutase or malondialdehyde in plasma were not affected by the different dietary lipid sources. Fish fed the LO diet had lower adipose triglyceride lipase and fatty acid synthase activities in liver than those fed the diets containing FO and RO, while the LO diet resulted in the highest hepatic carnitine palmitoultransferase-1 activity. Hepatic gene relative expression of adipose triglyceride lipase and carnitine palmitoyltransferase-1 in fish fed PO diet was significantly higher than all other groups, whereas fish fed the SO and LO diets had lower relative expression levels of

Different anthropometric adiposity measures and their association with cardiovascular disease risk factors: a meta-analysis.

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van Dijk, S B; Takken, T; Prinsen, E C; Wittink, H

2012-05-01

To investigate which anthropometric adiposity measure has the strongest association with cardiovascular disease (CVD) risk factors in Caucasian men and women without a history of CVD. Systematic review and meta-analysis. We searched databases for studies reporting correlations between anthropometric adiposity measures and CVD risk factors in Caucasian subjects without a history of CVD. Body mass index (BMI), waist circumference, waist-to-hip ratio, waist-to-height ratio and body fat percentage were considered the anthropometric adiposity measures. Primary CVD risk factors were: systolic blood pressure, diastolic blood pressure, high density lipoprotein (HDL) cholesterol, triglycerides and fasting glucose. Two independent reviewers performed abstract, full text and data selection. Twenty articles were included describing 21,618 males and 24,139 females. Waist circumference had the strongest correlation with all CVD risk factors for both men and women, except for HDL and LDL in men. When comparing BMI with waist circumference, the latter showed significantly better correlations to CVD risk factors, except for diastolic blood pressure in women and HDL and total cholesterol in men. We recommend the use of waist circumference in clinical and research studies above other anthropometric adiposity measures, especially compared with BMI, when evaluating CVD risk factors.

Release of endothelial cell lipoprotein lipase by plasma lipoproteins and free fatty acids

International Nuclear Information System (INIS)

Saxena, U.; Witte, L.D.; Goldberg, I.J.

1989-01-01

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 125 I-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

Fat digestion and absorption in spice-pretreated rats.

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Prakash, Usha N S; Srinivasan, Krishnapura

2012-02-01

A few common spices are known to stimulate secretion of bile with higher amount of bile acids which play a major role in digestion and absorption of dietary lipids. It would be appropriate to verify if these spices enable efficient digestion and absorption during high-fat intake. In this context, dietary ginger (0.05%), piperine (0.02%), capsaicin (0.015%), and curcumin (0.5%) were examined for their influence on bile secretion, digestive enzymes of pancreas and absorption of dietary fat in high-fat (30%) fed Wistar rats for 8 weeks. These spices enhanced the activity of pancreatic lipase, amylase, trypsin and chymotrypsin by 22-57%, 32-51%, 63-81% and 12-38%, respectively. Dietary intake of spices along with high-fat enhanced fat absorption. These dietary spices increased bile secretion with higher bile acid content. Stimulation of lipid mobilisation from adipose tissue was suggested by the decrease in perirenal adipose tissue weight by dietary capsaicin and piperine. This was also accompanied by prevention of the accumulation of triglyceride in liver and serum in high-fat fed rats. Activities of key lipogenic enzymes in liver were reduced which was accompanied by an increased activity of hormone-sensitive lipase. Thus, dietary ginger and other spice compounds enhance fat digestion and absorption in high-fat fed situation through enhanced secretion of bile salts and a stimulation of the activity pancreatic lipase. At the same time, the energy expenditure is facilitated by these spices to prevent the accumulation of absorbed fat. Copyright © 2011 Society of Chemical Industry.

Seed lipases: sources, applications and properties - a review

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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.

Structural characterization of MAPLE deposited lipase biofilm

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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.

Characterization of alkaline lipase from Fusarium oxysporum and the effect of different surfactants and detergents on the enzyme activity Caracterização de lipase alcalina de Fusarium oxysporum e o efeito de diferentes surfactantes e detergentes sobre a atividade enzimática

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Janaina Nicanuzia dos Prazeres

2006-12-01

Full Text Available Nowadays, there is a tendency of use of low temperature in laundry cleaning for both environmental and economical reasons, which makes the use of enzymes in detergent products indispensable. Since lipases are efficient catalyst both in solution and at the water-liquid interface, they are potentially suitable for lipid stain removal applications in industrial laundry and household detergents. The effect of different commercial detergents and surfactants on enzymatic activity of lipase from Fusarium oxysporum was observed through p-nitrophenylpalmitate (pNPP assay. The enzyme was compatible with various ionic and non-ionic surfactants as well as commercial detergents. Lipase activity was strongly inhibited by Sodium Dodecyl Sulphate (SDS, but not by Triton X-100 and Triton X-114. The best assay conditions observed for this lipase were pH 8.0 and 50ºC. The enzyme was stable at alkaline pH and remained 93% of residual activity during 1 h incubation at 60ºC. The highest lipase activity was measured with triglycerides of middle and long chain fatty acids (C8-C18. This enzyme showed a variable specifity/hydrolytic activity towards various fats and oils. All these properties and its resistance towards various surfactants and tolerance to commercial detergents make this lipase a potential additive for detergent formulation.Atualmente, há uma tendência de utilizar baixas temperaturas em limpeza de lavanderia por razões ambientais e econômicas, situações estas que tornam indispensáveis o uso de enzimas em produtos detergentes. Devido às lipases serem excelentes catalisadoras em soluções e em interface água-óleo, elas são potencialmente apropriadas para aplicação na remoção de manchas de gorduras em lavanderia industrial e detergentes domésticos. O efeito de diferentes detergentes comerciais e surfactantes sobre a atividade enzimática da lipase de Fusarium oxysporum foi observado através de ensaios com p-nitrofenilpalmitato (pNPP. A

Lipase or amylase for the diagnosis of acute pancreatitis?

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Ismail, Ola Z; Bhayana, Vipin

2017-12-01

Acute pancreatitis is a rapid onset of inflammation of the pancreas causing mild to severe life threatening conditions [1, 2]. In Canada, acute pancreatitis is the 5th most expensive digestive disease in Canada with a considerable economic burden on the health care system [3]. The diagnosis of acute pancreatitis is usually based on the presence of abdominal pain and elevated levels of serum amylase and/or lipase. Many health care centers use either serum amylase, lipase or both to diagnose acute pancreatitis without considering which one could provide a better diagnostic accuracy. The aim of this review is to investigate whether serum lipase alone is a sufficient biomarker for the diagnosis of acute pancreatitis. We have examined various studies looking at the utilization, sensitivity, specificity and cost associated savings of lipase and amylase in the diagnosis of acute pancreatitis. When comparing different studies, serum lipase offers a higher sensitivity than serum amylase in diagnosing acute pancreatitis. Lipase also offers a larger diagnostic window than amylase since it is elevated for a longer time, thus allowing it to be a useful diagnostic biomarker in early and late stages of acute pancreatitis. Several recent evidence-based guidelines recommend the use of lipase over amylase. Nevertheless, both lipase and amylase alone lack the ability to determine the severity and etiology of acute pancreatitis. The co-ordering of both tests has shown little to no increase in the diagnostic sensitivity and specificity. Thus, unnecessary testing and laboratory expenditures can be reduced by testing lipase alone. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Inhibition of lipases from Chromobacterium viscosum and Rhizopus oryzae by tetrahydrolipstatin.

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Potthoff, A P; Haalck, L; Spener, F

1998-01-15

Tetrahydrolipstatin is known as an inhibitor for pancreatic lipase but not for microbial lipases. In this paper we demonstrate that in the presence of water-insoluble substrates like tributyrin or olive oil, tetrahydrolipstatin inhibits the lipases of Chromobacterium viscosum and Rhizopus oryzae, although with different potency. In contrast to porcine pancreatic lipase, which forms an irreversible and covalent enzyme-inhibitor complex with tetrahydrolipstatin, the inhibition of the microbial lipases is reversible as the inhibitor can be removed from the enzyme-inhibitor complex by solvent extraction. Moreover, after inhibition of Chromobacterium viscosum lipase tetrahydrolipstatin remains chemically unchanged.

Clinical usefulness of lipid ratios, visceral adiposity indicators, and the triglycerides and glucose index as risk markers of insulin resistance.

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Du, Tingting; Yuan, Gang; Zhang, Muxun; Zhou, Xinrong; Sun, Xingxing; Yu, Xuefeng

2014-10-20

To directly compare traditional lipid ratios (total cholesterol [TC]/high density lipoprotein cholesterol [HDL-C], non-HDL-C/HDL-C, low density lipoprotein cholesterol [LDL-C]/HDL-C, and triglycerides [TG]/HDL-C), apolipoprotein B (apoB)/apolipoprotein A-I (apoA-I) ratio, visceral adiposity index (VAI), lipid accumulation product (LAP), and the product of TG and fasting glucose (TyG) for strength and independence as risk factors for insulin resistance (IR). We conducted a cross-sectional analysis of 7629 Chinese adults using data from the China Health and Nutrition Survey 2009. For all lipid ratios (traditional lipid ratios and apoB/apoA-I), among both sexes, TG/HDL-C explained the most additional percentage of variation in HOMA-IR (2.9% in men, and 2.3% in women); for all variables of interest, the variability in HOMA-IR explained by VAI and TG/HDL-C were comparable; TyG had the most significant association with HOMA-IR, which explained 9.1% for men and 7.8% for women of the variability in HOMA-IR. Logistic regression analysis showed the similar patterns. Receiver operating characteristic (ROC) curve analysis showed that, among both sexes, TG/HDL-C was a better discriminator of IR than apoB/apoA-I; the area under the ROC curve (AUC) for VAI (0.695 in men and 0.682 in women) was greater than that for TG/HDL-C (AUC 0.665 in men and 0.664 in women); TyG presented the greatest value of AUC (0.709 in men and 0.711 in women). The apoB/apoA-I performs no better than any of the traditional lipid ratios in correlating with IR. The TG/HDL-C, VAI and TyG are better markers for early identification of IR individuals.

Differences between men and women in the regulation of adipose 11β-HSD1 and in its association with adiposity and insulin resistance.

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DeSchoolmeester, J; Palming, J; Persson, T; Pereira, M J; Wallerstedt, E; Brown, H; Gill, D; Renström, F; Lundgren, M; Svensson, M K; Rees, A; Eriksson, J W

2013-11-01

This study explored sex differences in 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity and gene expression in isolated adipocytes and adipose tissue (AT), obtained via subcutaneous biopsies from non-diabetic subjects [58 M, 64 F; age 48.3 ± 15.3 years, body mass index (BMI) 27.2 ± 3.9 kg/m²]. Relationships with adiposity and insulin resistance (IR) were addressed. Males exhibited higher 11β-HSD1 activity in adipocytes than females, but there was no such difference for AT. In both men and women, adipocyte 11β-HSD1 activity correlated positively with BMI, waist circumference, % body fat, adipocyte size and with serum glucose, triglycerides and low-density lipoprotein:high-density lipoprotein (LDL:HDL) ratio. Positive correlations with insulin, HOMA-IR and haemoglobin A1c (HbA1c) and a negative correlation with HDL-cholesterol were significant only in males. Conversely, 11β-HSD1 activity in AT correlated with several markers of IR and adiposity in females but not in males, but the opposite pattern was found with respect to 11β-HSD1 mRNA expression. This study suggests that there are sex differences in 11β-HSD1 regulation and in its associations with markers of obesity and IR. © 2013 John Wiley & Sons Ltd.

Structure of Human Pancreatic Lipase-Related Protein 2 with the Lid in an Open Conformation

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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.

21 CFR 184.1420 - Lipase enzyme preparation derived from Rhizopus niveus.

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2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Lipase enzyme preparation derived from Rhizopus... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1420 Lipase enzyme preparation derived from Rhizopus niveus. (a) Lipase enzyme preparation contains lipase enzyme (CAS Reg. No...

Production of lipase free of citrinin by Penicillium citrinum.

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Pimentel, M C; Melo, E H; Lima Filho, J L; Durán, N

1996-02-01

Lipase (Glycerol ester hydrolase E.G. 3.1.1.3) from a Brazilian strain of Penicillium citrinum free of the mycotoxin citrinin has been investigated. Citrinin production was inhibited by using culture medium containing olive oil, soybean oil and corn oil as carbon sources. Potassium concentration and pH play an important role in citrinin production. Potassium concentration lower than 30 mM and pH below 4.5 inhibited the mycotoxin production. P. citrinum produced lipase free of extraneous proteins and citrinin when cultured using, as nitrogen source, ammonium sulphate (lipase activity of 7.88 U/mg) and yeast extract (lipase activity of 4.95 U/mg) with olive oil as carbon source. This data is relevant to the larger scale production of lipases for food technology applications, from Penicillium citrinum.

Resistance to diet-induced adiposity in cannabinoid receptor-1 deficient mice is not due to impaired adipocyte function

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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.

Waist Circumference, Body Mass Index, and Other Measures of Adiposity in Predicting Cardiovascular Disease Risk Factors among Peruvian Adults

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K. M. Knowles

2011-01-01

Full Text Available Objectives. To examine the extent to which measures of adiposity can be used to predict selected components of metabolic syndrome (MetS and elevated C-reactive protein (CRP. Methods. A total of 1,518 Peruvian adults were included in this study. Waist circumference (WC, body mass index (BMI, waist-hip ratio (WHR, waist-height ratio (WHtR, and visceral adiposity index (VAI were examined. The prevalence of each MetS component was determined according to tertiles of each anthropometric measure. ROC curves were used to evaluate the extent to which measures of adiposity can predict cardiovascular risk. Results. All measures of adiposity had the strongest correlation with triglyceride concentrations (TG. For both genders, as adiposity increased, the prevalence of Mets components increased. Compared to individuals with low-BMI and low-WC, men and women with high-BMI and high- WC had higher odds of elevated fasting glucose, blood pressure, TG, and reduced HDL, while only men in this category had higher odds of elevated CRP. Overall, the ROCs showed VAI, WC, and WHtR to be the best predictors for individual MetS components. Conclusions. The results of our study showed that measures of adiposity are correlated with cardiovascular risk although no single adiposity measure was identified as the best predictor for MetS.

Engineering Lipases: walking the fine line between activity and stability

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Dasetty, Siva; Blenner, Mark A.; Sarupria, Sapna

2017-11-01

Lipases are enzymes that hydrolyze lipids and have several industrial applications. There is a tremendous effort in engineering the activity, specificity and stability of lipases to render them functional in a variety of environmental conditions. In this review, we discuss the recent experimental and simulation studies focused on engineering lipases. Experimentally, mutagenesis studies have demonstrated that the activity, stability, and specificity of lipases can be modulated by mutations. It has been particularly challenging however, to elucidate the underlying mechanisms through which these mutations affect the lipase properties. We summarize results from experiments and molecular simulations highlighting the emerging picture to this end. We end the review with suggestions for future research which underscores the delicate balance of various facets in the lipase that affect their activity and stability necessitating the consideration of the enzyme as a network of interactions.

Optimization of lipase-catalyzed biodiesel by isopropanolysis in a continuous packed-bed reactor using response surface methodology.

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Chang, Cheng; Chen, Jiann-Hwa; Chang, Chieh-Ming J; Wu, Tsung-Ta; Shieh, Chwen-Jen

2009-10-31

Isopropanolysis reactions were performed using triglycerides with immobilized lipase in a solvent-free environment. This study modeled the degree of isopropanolysis of soybean oil in a continuous packed-bed reactor when Novozym 435 was used as the biocatalyst. Response surface methodology (RSM) and three-level-three-factor Box-Behnken design were employed to evaluate the effects of synthesis parameters, reaction temperature ( degrees C), flow rate (mL/min) and substrate molar ratio of isopropanol to soybean oil, on the percentage molar conversion of biodiesel by transesterification. The results show that flow rate and temperature have a significant effect on the percentage of molar conversion. On the basis of ridge max analysis, the optimum conditions for synthesis were as follows: flow rate 0.1 mL/min, temperature 51.5 degrees C and substrate molar ratio 1:4.14. The predicted value was 76.62+/-1.52% and actual experimental value was 75.62+/-0.81% molar conversion. Moreover, continuous enzymatic process for seven days did not show any appreciable decrease in the percent of molar conversion (75%). This work demonstrates the applicability of lipase catalysis to prepare isopropyl esters by transesterification in solvent-free system with a continuous packed-bed reactor for industrial production.

Genetics Home Reference: lysosomal acid lipase deficiency

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... lipase deficiency develop multi-organ failure and severe malnutrition and generally do not survive past 1 year. In the later-onset form of lysosomal acid lipase deficiency , signs and symptoms vary and usually begin in mid-childhood, although they can appear anytime up to late ...

Structural studies on lipoprotein lipase

International Nuclear Information System (INIS)

Socorro, L.

1985-01-01

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 [ 3 H]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% [ 3 H]dpm) were used for further purification. Differential extraction of the [ 3 H]-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

Sleep deprivation affects inflammatory marker expression in adipose tissue

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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.

Lipase from a Brazilian strain of Penicillium citrinum.

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Pimentel, M C; Krieger, N; Coelho, L C; Fontana, J O; Melo, E H; Ledingham, W M; Lima Filho, J L

1994-10-01

A lipases (glycerol ester hydrolases E. C. 3.1.1.3) from a brazilian strain of Penicillium citrinum has been investigated. When the microorganism was cultured in the simple medium (1.0% olive oil and 0.5% yeast extract), using olive oil in as carbon source in the inocula, the enzyme extracted showed maximum activity (409 IU/mL). In addition, decrease of yeast extract concentration also reduces the lipase activity. Nevertheless, when yeast extract was replaced by ammonium sulfate, no activity was detected. Purification by precipitation with ammonium sulfate showed best activity in the 40-60% fraction. The optimum temperature for enzyme activity was found in the range of 34-37 degrees C. However, after 30 min at 60 degrees C, the enzyme was completely inactivated. The enzyme showed optimum at pH 8.0. The dried concentrated fraction (after dialysis and lyophilization) maintained its lipase activity at room temperature (28 degrees C) for 8 mo. This result in lipase stability suggests an application of lipases from P. citrinum in detergents and other products that require a high stability at room temperature.

Dependency of water concentration on ethanolysis of trioleoylglycerol by lipases

DEFF Research Database (Denmark)

Piyatheerawong, W.; Iwasaki, Y; Xu, Xuebing

2004-01-01

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...

Bioremediation of cooking oil waste using lipases from wastes.

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Clarissa Hamaio Okino-Delgado

Full Text Available Cooking oil waste leads to well-known environmental impacts and its bioremediation by lipase-based enzymatic activity can minimize the high cytotoxic potential. In addition, they are among the biocatalysts most commercialized worldwide due to the versatility of reactions and substrates. However, although lipases are able to process cooking oil wastes, the products generated from this process do not necessarily become less toxic. Thus, the aim of the current study is to analyze the bioremediation of lipase-catalyzed cooking oil wastes, as well as their effect on the cytotoxicity of both the oil and its waste before and after enzymatic treatment. Thus, assessed the post-frying modification in soybean oil and in its waste, which was caused by hydrolysis reaction catalyzed by commercial and home-made lipases. The presence of lipases in the extracts obtained from orange wastes was identified by zymography. The profile of the fatty acid esters formed after these reactions was detected and quantified through gas chromatography and fatty acids profile compared through multivariate statistical analyses. Finally, the soybean oil and its waste, with and without enzymatic treatment, were assessed for toxicity in cytotoxicity assays conducted in vitro using fibroblast cell culture. The soybean oil wastes treated with core and frit lipases through transesterification reaction were less toxic than the untreated oils, thus confirming that cooking oil wastes can be bioremediated using orange lipases.

Screening of thermophilic neutral lipase-producing Pseudomonas ...

African Journals Online (AJOL)

From oil-contaminated soil, three lipase-producing microorganisms were selected as good lipase producers using rhodamine B-olive oil plate agar and they were identified as from Pseudomonas, Burkholderia and Klebsiella genera by morphology, biochemical characterization and 16S rRNA gene sequencing. Among the ...

Adipose tissue invariant NKT cells protect against diet-induced obesity and metabolic disorder through regulatory cytokine production.

LENUS (Irish Health Repository)

Lynch, Lydia

2012-09-21

Invariant natural killer T (iNKT) cells are evolutionarily conserved innate T cells that influence inflammatory responses. We have shown that iNKT cells, previously thought to be rare in humans, were highly enriched in human and murine adipose tissue, and that as adipose tissue expanded in obesity, iNKT cells were depleted, correlating with proinflammatory macrophage infiltration. iNKT cell numbers were restored in mice and humans after weight loss. Mice lacking iNKT cells had enhanced weight gain, larger adipocytes, fatty livers, and insulin resistance on a high-fat diet. Adoptive transfer of iNKT cells into obese mice or in vivo activation of iNKT cells via their lipid ligand, alpha-galactocylceramide, decreased body fat, triglyceride levels, leptin, and fatty liver and improved insulin sensitivity through anti-inflammatory cytokine production by adipose-derived iNKT cells. This finding highlights the potential of iNKT cell-targeted therapies, previously proven to be safe in humans, in the management of obesity and its consequences.

The Role of Adiposity in Cardiometabolic Traits: A Mendelian Randomization Analysis

Science.gov (United States)

Ploner, Alexander; Fischer, Krista; Horikoshi, Momoko; Sarin, Antti-Pekka; Thorleifsson, Gudmar; Ladenvall, Claes; Kals, Mart; Kuningas, Maris; Draisma, Harmen H. M.; Ried, Janina S.; van Zuydam, Natalie R.; Huikari, Ville; Mangino, Massimo; Sonestedt, Emily; Benyamin, Beben; Nelson, Christopher P.; Rivera, Natalia V.; Kristiansson, Kati; Shen, Huei-yi; Havulinna, Aki S.; Dehghan, Abbas; Donnelly, Louise A.; Kaakinen, Marika; Nuotio, Marja-Liisa; Robertson, Neil; de Bruijn, Renée F. A. G.; Ikram, M. Arfan; Amin, Najaf; Balmforth, Anthony J.; Braund, Peter S.; Doney, Alexander S. F.; Döring, Angela; Elliott, Paul; Esko, Tõnu; Franco, Oscar H.; Gretarsdottir, Solveig; Hartikainen, Anna-Liisa; Heikkilä, Kauko; Herzig, Karl-Heinz; Holm, Hilma; Hottenga, Jouke Jan; Hyppönen, Elina; Illig, Thomas; Isaacs, Aaron; Isomaa, Bo; Karssen, Lennart C.; Kettunen, Johannes; Koenig, Wolfgang; Kuulasmaa, Kari; Laatikainen, Tiina; Laitinen, Jaana; Lindgren, Cecilia; Lyssenko, Valeriya; Läärä, Esa; Rayner, Nigel W.; Männistö, Satu; Pouta, Anneli; Rathmann, Wolfgang; Rivadeneira, Fernando; Ruokonen, Aimo; Savolainen, Markku J.; Sijbrands, Eric J. G.; Small, Kerrin S.; Smit, Jan H.; Steinthorsdottir, Valgerdur; Syvänen, Ann-Christine; Taanila, Anja; Tobin, Martin D.; Uitterlinden, Andre G.; Willems, Sara M.; Willemsen, Gonneke; Witteman, Jacqueline; Perola, Markus; Evans, Alun; Ferrières, Jean; Virtamo, Jarmo; Kee, Frank; Tregouet, David-Alexandre; Arveiler, Dominique; Amouyel, Philippe; Ferrario, Marco M.; Brambilla, Paolo; Hall, Alistair S.; Heath, Andrew C.; Madden, Pamela A. F.; Martin, Nicholas G.; Montgomery, Grant W.; Whitfield, John B.; Jula, Antti; Knekt, Paul; Oostra, Ben; van Duijn, Cornelia M.; Penninx, Brenda W. J. H.; Davey Smith, George; Kaprio, Jaakko; Samani, Nilesh J.; Gieger, Christian; Peters, Annette; Wichmann, H.-Erich; Boomsma, Dorret I.; de Geus, Eco J. C.; Tuomi, TiinaMaija; Power, Chris; Hammond, Christopher J.; Spector, Tim D.; Lind, Lars; Orho-Melander, Marju; Palmer, Colin Neil Alexander; Morris, Andrew D.; Groop, Leif; Järvelin, Marjo-Riitta; Salomaa, Veikko; Vartiainen, Erkki; Hofman, Albert; Ripatti, Samuli; Metspalu, Andres; Thorsteinsdottir, Unnur; Stefansson, Kari; Pedersen, Nancy L.; McCarthy, Mark I.; Ingelsson, Erik; Prokopenko, Inga

2013-01-01

Background The association between adiposity and cardiometabolic traits is well known from epidemiological studies. Whilst the causal relationship is clear for some of these traits, for others it is not. We aimed to determine whether adiposity is causally related to various cardiometabolic traits using the Mendelian randomization approach. Methods and Findings We used the adiposity-associated variant rs9939609 at the FTO locus as an instrumental variable (IV) for body mass index (BMI) in a Mendelian randomization design. Thirty-six population-based studies of individuals of European descent contributed to the analyses. Age- and sex-adjusted regression models were fitted to test for association between (i) rs9939609 and BMI (n = 198,502), (ii) rs9939609 and 24 traits, and (iii) BMI and 24 traits. The causal effect of BMI on the outcome measures was quantified by IV estimators. The estimators were compared to the BMI–trait associations derived from the same individuals. In the IV analysis, we demonstrated novel evidence for a causal relationship between adiposity and incident heart failure (hazard ratio, 1.19 per BMI-unit increase; 95% CI, 1.03–1.39) and replicated earlier reports of a causal association with type 2 diabetes, metabolic syndrome, dyslipidemia, and hypertension (odds ratio for IV estimator, 1.1–1.4; all p<0.05). For quantitative traits, our results provide novel evidence for a causal effect of adiposity on the liver enzymes alanine aminotransferase and gamma-glutamyl transferase and confirm previous reports of a causal effect of adiposity on systolic and diastolic blood pressure, fasting insulin, 2-h post-load glucose from the oral glucose tolerance test, C-reactive protein, triglycerides, and high-density lipoprotein cholesterol levels (all p<0.05). The estimated causal effects were in agreement with traditional observational measures in all instances except for type 2 diabetes, where the causal estimate was larger than the observational

Frozen Microemulsions for MAPLE Immobilization of Lipase

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Valeria Califano

2017-12-01

Full Text Available Candida rugosa lipase (CRL was deposited by matrix assisted pulsed laser evaporation (MAPLE in order to immobilize the enzyme with a preserved native conformation, which ensures its catalytic functionality. For this purpose, the composition of the MAPLE target was optimized by adding the oil phase pentane to a water solution of the amino acid 3-(3,4-dihydroxyphenyl-2-methyl-l-alanine (m-DOPA, giving a target formed by a frozen water-lipase-pentane microemulsion. Fourier transform infrared (FTIR spectroscopy and atomic force microscopy (AFM were used to investigate the structure of MAPLE deposited lipase films. FTIR deconvolution of amide I band indicated a reduction of unfolding and aggregation, i.e., a better preserved lipase secondary structure in the sample deposited from the frozen microemulsion target. AFM images highlighted the absence of big aggregates on the surface of the sample. The functionality of the immobilized enzyme to promote transesterification was determined by thin layer chromatography, resulting in a modified specificity.

Microbial lipases: Production, properties and biotechnological applications

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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.

Karakterisasi ekstrak kasar lipase Rhizopus stolonifer UICC 137

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Sri Sumiarsih

2001-12-01

Full Text Available There is an increasing commercial interest in enzymatic production of biologically active component, because there are a number of well-known advantages compared to chemical synthesis. One of the most valuable synthetic features of enzyme is their ability to discriminate between enantiomers of racemic substrates. Lipase have become of great interest to the chemical industries wing their usefulness in both hydrolytic and synthesis reactions. The aim of this work was to study the production of lipase by Rhizopus stolonifer UICC 137, and determine the crude lipase preparation characteristics. The lipolytic activity was determined by titrimetric method toward oil-arabic gum emultion as a substrate. The strain produced lipase at appreciable lipolytic when cultivated for 72 hours in medium containing 3% glucose and 1% olive oil. Our data suggest that the strain produced lipase since the exponential phase of its growth. Lipase with optimum lipolytic activity was obtained at late stationary phase. The optimum condition for lipolytic activity measurement were pH of 7.5 and temperature 37oC, the crude enzyme had a specific activity 20.2 unit/ mg protein, the Vmax was 15.1 mol/ min and KM was 12.5 mg/ ml. The crude enzyme retained 79.9%, 68.0% and 52.6% of its lipolytic activity, when incubated for 90 minutes at temperature of 40, 50, and 60oC respectively.

Increased Visceral Adipose Tissue Is an Independent Predictor for Future Development of Atherogenic Dyslipidemia.

Science.gov (United States)

Hwang, You-Cheol; Fujimoto, Wilfred Y; Hayashi, Tomoshige; Kahn, Steven E; Leonetti, Donna L; Boyko, Edward J

2016-02-01

Atherogenic dyslipidemia is frequently observed in persons with a greater amount of visceral adipose tissue (VAT). However, it is still uncertain whether VAT is independently associated with the future development of atherogenic dyslipidemia. The aim of this study was to determine whether baseline and changes in VAT and subcutaneous adipose tissue (SAT) are associated with future development of atherogenic dyslipidemia independent of baseline lipid levels and standard anthropometric indices. Community-based prospective cohort study with 5 years of follow-up. A total of 452 Japanese Americans (240 men, 212 women), aged 34-75 years were assessed at baseline and after 5 years of follow-up. Abdominal fat areas were measured by computed tomography. Atherogenic dyslipidemia was defined as one or more abnormalities in high-density lipoprotein (HDL) cholesterol, triglycerides, or non-HDL cholesterol levels. Baseline VAT and change in VAT over 5 years were independently associated with log-transformed HDL cholesterol, log-transformed triglyceride, and non-HDL cholesterol after 5 years (standardized β = -0.126, 0.277, and 0.066 for baseline VAT, respectively, and -0.095, 0.223, and 0.090 for change in VAT, respectively). However, baseline and change in SAT were not associated with any future atherogenic lipid level. In multivariate logistic regression analysis, incremental change in VAT (odds ratio [95% confidence interval], 1.73 [1.20-2.48]; P = .003), triglycerides (4.01 [1.72-9.33]; P = .001), HDL cholesterol (0.32 [0.18-0.58]; P dyslipidemia independent of age, sex, diastolic blood pressure, homeostasis model assessment insulin resistance, body mass index (BMI), change in BMI, SAT, and baseline atherogenic lipid levels. Baseline and change in VAT were independent predictors for future development of atherogenic dyslipidemia. However, BMI, waist circumference, and SAT were not associated with future development of atherogenic dyslipidemia.

Mutation induced enhanced biosynthesis of lipase | Bapiraju ...

African Journals Online (AJOL)

The purpose of the present investigation is to enhance production of biomedically important enzyme lipase by subjecting the indigenous lipase producing strain Rhizopus sp. BTS-24 to improvement by natural selection and random mutagenesis (UV and N-methyl-N'-nitro-N-nitroso guanidine, NTG). The isolation of mutants ...

Triglycerides: Why Do They Matter?

Science.gov (United States)

... high level of triglycerides, a type of fat (lipid) in your blood, can increase your risk of ... triglycerides, too. Triglycerides are a type of fat (lipid) found in your blood. When you eat, your ...

Lipase and esterase: to what extent can this classification be applied accurately?

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Danielle Branta Lopes

2011-09-01

Full Text Available Enzyme technology is an ever-growing field of knowledge and, in recent years, this technology has raised renewed interest, due to the search for new paradigms in several productive processes. Lipases, esterases and cutinases are enzymes used in a wide range of processes involving synthesis and hydrolysis reactions. The objective of this work was to investigate and compare the specific lipase and esterase activities of five enzymes - four already classified as lipases and one classified as cutinase - in the presence of natural and synthetic substrates. All tested enzymes presented both esterase and lipase specific activities. The highest specific esterase activity was observed for Aspergillus 1068 lipase in natural substrate and for F. oxysporum cutinase in synthetic substrate, while the highest specific lipase activity was observed for Geotrichum sp. lipase in natural substrate and for F. oxysporum cutinase in synthetic substrate. These results display some interface-independent lipolytic activity for all lipases tested. This is in accordance with the rationale that a new and broader definition of lipases may be necessary.

Lipase inactivation in wheat germ by gamma irradiation

International Nuclear Information System (INIS)

Jha, Pankaj Kumar; Kudachikar, V.B.; Kumar, Sourav

2013-01-01

An attempt was made to improve the shelf life of wheat germ by optimizing processing conditions involving γ-irradiation. Studies were carried out to investigate the effect of γ-irradiation (0–30 kGy doses) on the chemical composition of wheat germ with respect to variation in moisture, total ash, crude fat, free fatty acid, protein and lipase activity. The results demonstrate that shelf stability of wheat germ was achieved by inactivation of lipase at doses of γ-irradiation greater than 12 kGy. - Highlights: Ø γ-irradiation was found to inactivate Lipase present in Wheat Germ. Ø The treatment did not result in significant changes in Total Ash, Moisture and Protein Content of Wheat Germ. Ø The irradiation at 30 kGy resulted in 31.2 % inactivation of Lipase in Wheat Germ

Production of Cold Active Lipase from Bacillus sp.

OpenAIRE

Yasemin, Sara; Arabacı, Nihan; Korkmaz Güvenmez, Hatice

2018-01-01

A cold active lipase producing Bacillus sp. strains were isolated from sewage of oil. Bacillus sp. strain SY-7 was determined as the best lipase producing isolate. The highest enzyme production was found at 20°C and pH 8.0 on tributyrin media. Analyses of molecular mass of the partial purified lipase was carried out by SDS-PAGE which revealed a single band as 110.5 kDa. The enzyme activity and stability were determined by spectrophotometric and titrimetric methods. The enzyme was active betwe...

Zymography Detection of a Bacterial Extracellular Thermoalkaline Esterase/Lipase Activity.

Science.gov (United States)

Tapizquent, María; Fernández, Marleny; Barreto, Georgina; Hernández, Zully; Contreras, Lellys M; Kurz, Liliana; Wilkesman, Jeff

2017-01-01

Lipases are esterases that occur widely in nature, yet those with commercial relevance are exclusively from microbial origin. Glycerol and long-chain fatty acids are the products after hydrolysis of esters bonds in saponifiable lipids catalyzed by lipases. In this work, we describe lipase/esterase activity contained in cell-free fractions from thermophilic bacteria, cultured in medium containing olive oil. Analysis of the cell-free fractions by electrotransference zymography, using tributyrin as substrate, revealed bands corresponding to lipase activity. The method is simple, fast, and inexpensive.

Purification and characterization of a new cold active lipase, EnL A ...

African Journals Online (AJOL)

Search of lipase engineering data base (LED) revealed that this protein belongs to a newly introduced super family of Candida antarctica lipase A like and to the homologous family of Aspergillus lipase like. Key words: Cold active lipase, Emericella nidulans, hydrophobic interaction chromatography, Candida antarctica ...

Realm of Thermoalkaline Lipases in Bioprocess Commodities

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Ahmad Firdaus B. Lajis

2018-01-01

Full Text Available For decades, microbial lipases are notably used as biocatalysts and efficiently catalyze various processes in many important industries. Biocatalysts are less corrosive to industrial equipment and due to their substrate specificity and regioselectivity they produced less harmful waste which promotes environmental sustainability. At present, thermostable and alkaline tolerant lipases have gained enormous interest as biocatalyst due to their stability and robustness under high temperature and alkaline environment operation. Several characteristics of the thermostable and alkaline tolerant lipases are discussed. Their molecular weight and resistance towards a range of temperature, pH, metal, and surfactants are compared. Their industrial applications in biodiesel, biodetergents, biodegreasing, and other types of bioconversions are also described. This review also discusses the advance of fermentation process for thermostable and alkaline tolerant lipases production focusing on the process development in microorganism selection and strain improvement, culture medium optimization via several optimization techniques (i.e., one-factor-at-a-time, surface response methodology, and artificial neural network, and other fermentation parameters (i.e., inoculums size, temperature, pH, agitation rate, dissolved oxygen tension (DOT, and aeration rate. Two common fermentation techniques for thermostable and alkaline tolerant lipases production which are solid-state and submerged fermentation methods are compared and discussed. Recent optimization approaches using evolutionary algorithms (i.e., Genetic Algorithm, Differential Evolution, and Particle Swarm Optimization are also highlighted in this article.

Realm of Thermoalkaline Lipases in Bioprocess Commodities.

Science.gov (United States)

Lajis, Ahmad Firdaus B

2018-01-01

For decades, microbial lipases are notably used as biocatalysts and efficiently catalyze various processes in many important industries. Biocatalysts are less corrosive to industrial equipment and due to their substrate specificity and regioselectivity they produced less harmful waste which promotes environmental sustainability. At present, thermostable and alkaline tolerant lipases have gained enormous interest as biocatalyst due to their stability and robustness under high temperature and alkaline environment operation. Several characteristics of the thermostable and alkaline tolerant lipases are discussed. Their molecular weight and resistance towards a range of temperature, pH, metal, and surfactants are compared. Their industrial applications in biodiesel, biodetergents, biodegreasing, and other types of bioconversions are also described. This review also discusses the advance of fermentation process for thermostable and alkaline tolerant lipases production focusing on the process development in microorganism selection and strain improvement, culture medium optimization via several optimization techniques (i.e., one-factor-at-a-time, surface response methodology, and artificial neural network), and other fermentation parameters (i.e., inoculums size, temperature, pH, agitation rate, dissolved oxygen tension (DOT), and aeration rate). Two common fermentation techniques for thermostable and alkaline tolerant lipases production which are solid-state and submerged fermentation methods are compared and discussed. Recent optimization approaches using evolutionary algorithms (i.e., Genetic Algorithm, Differential Evolution, and Particle Swarm Optimization) are also highlighted in this article.

Liver lipase and high-density lipoprotein. Lipoprotein changes after incubation of human serum with rat liver lipase.

Science.gov (United States)

Groot, P H; Scheek, L M; Jansen, H

1983-05-16

Human sera were incubated with rat liver lipase after inactivation of lecithin:cholesterol acyltransferase, and the changes in serum lipoprotein composition were measured. In the presence of liver lipase serum triacylglycerol and phosphatidylcholine were hydrolyzed. The main changes in the concentrations of these lipids were found in the high-density lipoprotein fraction. Subfractionation of high-density lipoprotein by rate-zonal ultracentrifugation showed a prominent decrease in all constituents of high-density lipoprotein2, a smaller decrease in the 'light' high-density lipoprotein3 and an increase in the 'heavy' high-density lipoprotein3. These data support a concept in which liver lipase is involved in high-density lipoprotein2 phospholipid and triacylglycerol catabolism and suggest that as a result of this action high-density lipoprotein2 is converted into high-density lipoprotein3.

21 CFR 173.140 - Esterase-lipase derived from Mucor miehei.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Esterase-lipase derived from Mucor miehei. 173.140... HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.140 Esterase-lipase derived from Mucor miehei. Esterase-lipase enzyme, consisting of enzyme derived from Mucor miehei var. Cooney et Emerson by...

Beneficial effects of adding lipase enzyme to broiler diet

International Nuclear Information System (INIS)

Elbarkouky, E.M.A.

2005-01-01

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

Anti- and pro-lipase activity of selected medicinal, herbal and aquatic plants, and structure elucidation of an anti-lipase compound.

Science.gov (United States)

Ado, Muhammad Abubakar; Abas, Faridah; Mohammed, Abdulkarim Sabo; Ghazali, Hasanah M

2013-11-26

Plants that help in slowing down the digestion of triacylglycerols (TAGs) in the pancreas and small intestine of humans play an important role in the reduction of obesity. On the other hand, there may be plants or plant parts that stimulate intestinal lipolytic activity, thus contributing to greater TAG assimilation. The aim of this study was to evaluate the aqueous methanolic extracts of ninety eight (98) medicinal, herbal and aquatic plant materials from Malaysia for their effect on porcine pancreatic lipase (PPL) activity and to identify the structure of an anti-lipase compound from one of the sources. The degree of inhibition was also quantified as relative to orlistat activity against PPL (orlistat equivalents). Results revealed that while 19.4% of the extracts were found to have anti-lipase activity ≥80%, 12% were actually found to promote PPL activity. Twenty two percent (22.4%) exhibited moderate inhibition (41%-80%) and 2% were neutral toward PPL activity. The ripe fruit of Averrhoa carambola and the leaves of Archidendron jiringa (Jack) I.C Nielsen L. (jering), Cynometra cauliflora (nam-nam) and Aleurites moluccana (L.) Willd (candle nut/buah keras) had the highest (100%) anti-lipase activity and are equivalent to 0.11 µg orlistat/mL. Plants that stimulated lipase activity included Pimpinella anisum L. (aniseed/jintan manis), activating the enzyme by 186.5%. Kaempferol 3-O-rhamnoside was isolated from the ethyl acetate fraction of C. cauliflora leaves and found to be an active lipase inhibitor. The structure was elucidated using 1H-NMR, 13C-NMR and 2D-NMR analyses.

Biotechnological applications of halophilic lipases and thioesterases.

Science.gov (United States)

Schreck, Steven D; Grunden, Amy M

2014-02-01

Lipases and esterases are enzymes which hydrolyze ester bonds between a fatty acid moiety and an esterified conjugate, such as a glycerol or phosphate. These enzymes have a wide spectrum of use in industrial applications where their high activity, broad substrate specificity, and stability under harsh conditions have made them integral in biofuel production, textile processing, waste treatment, and as detergent additives. To date, these industrial applications have mainly leveraged enzymes from mesophilic and thermophilic organisms. However, increasingly, attention has turned to halophilic enzymes as catalysts in environments where high salt stability is desired. This review provides a brief overview of lipases and esterases and examines specific structural motifs and evolutionary adaptations of halophilic lipases. Finally, we examine the state of research involving these enzymes and provide an in-depth look at an exciting algal-based biofuel production system. This system uses a recombinant halophilic lipase to increase oil production efficiency by cleaving algal fatty acids from the acyl carrier protein, which eliminates feedback inhibition of fatty acid synthesis.

Hepatic ABC transporters and triglyceride metabolism.

Science.gov (United States)

Parks, John S; Chung, Soonkyu; Shelness, Gregory S

2012-06-01

Elevated plasma triglyceride and reduced HDL concentrations are prominent features of metabolic syndrome and type 2 diabetes. Individuals with Tangier disease also have elevated plasma triglyceride concentrations and very low HDL, resulting from mutations in ATP-binding cassette transporter A1 (ABCA1), an integral membrane protein that facilitates nascent HDL particle assembly. Past studies attributed the inverse relationship between plasma HDL and triglyceride to intravascular lipid exchange and catabolic events. However, recent studies also suggest that hepatic signaling and lipid mobilization and secretion may explain how HDL affects plasma triglyceride concentrations. Hepatocyte-specific ABCA1 knockout mice have markedly reduced plasma HDL and a two-fold increase in triglyceride due to failure to assemble nascent HDL particles by hepatocytes, causing increased catabolism of HDL apolipoprotein A-I and increased hepatic production of triglyceride-enriched VLDL. In-vitro studies suggest that nascent HDL particles may induce signaling to decrease triglyceride secretion. Inhibition of microRNA 33 expression in nonhuman primates augments hepatic ABCA1, genes involved in fatty acid oxidation, and decreases expression of lipogenic genes, causing increased plasma HDL and decreased triglyceride levels. New evidence suggests potential mechanisms by which hepatic ABCA1-mediated nascent HDL formation regulates VLDL-triglyceride production and contributes to the inverse relationship between plasma HDL and triglyceride.

Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae)

OpenAIRE

Dali, Seniwati; Patong, A. B. D. Rauf; Jalaluddin, M. Noor; Pirman; Hamzah, Baharuddin

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 ...

Hormone-sensitive lipase deficiency suppresses insulin secretion from pancreatic islets of Lepob/ob mice

International Nuclear Information System (INIS)

Sekiya, Motohiro; Yahagi, Naoya; Tamura, Yoshiaki; Okazaki, Hiroaki; Igarashi, Masaki; Ohta, Keisuke; Takanashi, Mikio; Kumagai, Masayoshi; Takase, Satoru; Nishi, Makiko; Takeuchi, Yoshinori; Izumida, Yoshihiko; Kubota, Midori; Ohashi, Ken; Iizuka, Yoko; Yagyu, Hiroaki; Gotoda, Takanari; Nagai, Ryozo; Shimano, Hitoshi; Yamada, Nobuhiro

2009-01-01

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 (Lep ob/ob /HSL -/- ) and explored the role of HSL in pancreatic β-cells in the setting of obesity. Lep ob/ob /HSL -/- developed elevated blood glucose levels and reduced plasma insulin levels compared with Lep ob/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 Lep ob/ob islets, leading to reduced glucose-stimulated insulin secretion. The deficiency of HSL also diminished the islet mass in Lep ob/ob mice due to decreased cell proliferation. In conclusion, HSL affects insulin secretary capacity especially in the setting of obesity.

Activities of asymmetric dimethylarginine-related enzymes in white adipose tissue are associated with circulating lipid biomarkers

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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.

Purification and characterization of halophilic lipase of Chromohalobacter sp. from ancient salt well.

Science.gov (United States)

Ai, Li; Huang, Yaping; Wang, Chuan

2018-06-04

A halophilic lipase (LipS2) was produced by Chromohalobacter canadensis strain which was isolated from ancient salt well of Zigong, China. LipS2 was purified to homogeneity and showed a single band with molecular mass of 58 kDa by SDS-PAGE. LipS2 preferred middle-to-long acyl chain esters with C14 triglycerides as optimum substrate. It was noteworthy that LipS2 displayed efficient hydrolysis activity to some vegetable oils which were composed of polyunsaturated fatty acid. LipS2 showed high activity in range of 2.5-3.5 M NaCl, no activity without salt. Optimum temperature and pH were 55 °C and pH 8.5, respectively. Notably, the thermostability and pH stability of LipS2, varying with salt concentration, reached optimum in the presence of 3.0 M NaCl. LipS2 was stimulated by Ca 2+ and Mg 2+ , inhibited by Zn 2+ , Cu 2+ , Mn 2+ , Fe 2+ , and Hg 2+ . Moreover, LipS2 displayed significant tolerance to organic solvents including methanol, ethanol, ethyl acetate and acetone, especially, LipS2 activity was enhanced markedly by the hexane and benzene. Non-ionic surfactants increased LipS2 activity, while ionic surfactants decreased activity. This was the first report on halophilic lipase of Chromohalobacter from ancient salt well. The results suggested that LipS2 may have considerable potential for biotechnological applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

KARAKTERISASI SIFAT-SIFAT BIOKIMIA EKSTRAK KASAR LIPASE EKSTRASELULER BAKTERI Azospirillum sp.PRD1

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Santi Nur Handayani

2011-11-01

Full Text Available 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 dari isolat lokal Laboratorium Mikrobiologi, Fakultas Biologi Universitas Jenderal Soedirman. Tujuan penelitian adalah untuk mendapatkan ekstrak kasar lipase dan menentukan karakteristik sifat-sifat biokimiawinya. Metode yang digunakan antara lain peremajaan bakteri Azospirillum sp.PRD1, dan produksi inokulum, penentuan waktu produksi optimum dan fase pertumbuhan bakteri, ekstraksi dan produksi ekstrak kasar lipase dan penentuan karakteristik sifat-sifat biokimiawinya. Hasil penelitian diperoleh ekstrak kasar lipase dari inokulum berumur 7 jam dan medium produksi dengan induser minyak zaitun yang diinkubasi selama 3 jam memiliki aktivitas spesifik 7,0547 Unit/mg. Lipase ekstrak kasar optimum pada pH 7, suhu 40 oC dan waktu inkubasi selama 25 menit. Lipase merupakan metaloenzim dengan kofaktor Zn2+ , Mn2+, Hg2+, Ca2+, Co2+ and Mg2+.

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)

Chang Wang, Huei-Hsiang Lisa.

1988-01-01

The cell killing process of 3T3 Swiss mouse fibroblasts stimulated by Ca 2+ plus A23187, a Ca 2+ 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 Ca 2+ -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 [ 3 H]glycerol and [ 3 H]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

Yeast Kluyveromyces lactis as host for expression of the bacterial lipase: cloning and adaptation of the new lipase gene from Serratia sp.

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Šiekštelė, Rimantas; Veteikytė, Aušra; Tvaska, Bronius; Matijošytė, Inga

2015-10-01

Many microbial lipases have been successfully expressed in yeasts, but not in industrially attractive Kluyveromyces lactis, which among other benefits can be cultivated on a medium supplemented with whey--cheap and easily available industrial waste. A new bacterial lipase from Serratia sp. was isolated and for the first time expressed into the yeast Kluyveromyces lactis by heterologous protein expression system based on a strong promoter of Kluyveromyces marxianus triosephosphate isomerase gene and signal peptide of Kluyveromyces marxianus endopolygalacturonase gene. In addition, the bacterial lipase gene was synthesized de novo by taking into account a codon usage bias optimal for K. lactis and was expressed into the yeast K. lactis also. Both resulting strains were characterized by high output level of the target protein secreted extracellularly. Secreted lipases were characterized for activity and stability.

Anti- and Pro-Lipase Activity of Selected Medicinal, Herbal and Aquatic Plants, and Structure Elucidation of an Anti-Lipase Compound

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Muhammad Abubakar Ado

2013-11-01

Full Text Available Plants that help in slowing down the digestion of triacylglycerols (TAGs in the pancreas and small intestine of humans play an important role in the reduction of obesity. On the other hand, there may be plants or plant parts that stimulate intestinal lipolytic activity, thus contributing to greater TAG assimilation. The aim of this study was to evaluate the aqueous methanolic extracts of ninety eight (98 medicinal, herbal and aquatic plant materials from Malaysia for their effect on porcine pancreatic lipase (PPL activity and to identify the structure of an anti-lipase compound from one of the sources. The degree of inhibition was also quantified as relative to orlistat activity against PPL (orlistat equivalents. Results revealed that while 19.4% of the extracts were found to have anti-lipase activity ≥80%, 12% were actually found to promote PPL activity. Twenty two percent (22.4% exhibited moderate inhibition (41%–80% and 2% were neutral toward PPL activity. The ripe fruit of Averrhoa carambola and the leaves of Archidendron jiringa (Jack I.C Nielsen L. (jering, Cynometra cauliflora (nam-nam and Aleurites moluccana (L. Willd (candle nut/buah keras had the highest (100% anti-lipase activity and are equivalent to 0.11 µg orlistat/mL. Plants that stimulated lipase activity included Pimpinella anisum L. (aniseed/jintan manis, activating the enzyme by 186.5%. Kaempferol 3-O-rhamnoside was isolated from the ethyl acetate fraction of C. cauliflora leaves and found to be an active lipase inhibitor. The structure was elucidated using 1H-NMR, 13C-NMR and 2D-NMR analyses.

Inhibition of gastric lipase as a mechanism for body weight and plasma lipids reduction in Zucker rats fed a rosemary extract rich in carnosic acid.

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María Romo Vaquero

Full Text Available BACKGROUND: Rosemary (Rosmarinus officinalis L. extracts (REs exhibit hepatoprotective, anti-obesity and anti-inflammatory properties and are widely used in the food industry. REs are rich in carnosic acid (CA and carnosol which may be responsible for some of the biological activities of REs. The aim of this study was to investigate whether inhibition of lipase activity in the gut may be a mechanism by which a RE enriched in CA (40% modulates body weight and lipids levels in a rat model of metabolic disorders and obesity. METHODS AND PRINCIPAL FINDINGS: RE was administered for 64 days to lean (fa/+ and obese (fa/fa female Zucker rats and body weight, food intake, feces weight and blood biochemical parameters were monitored throughout the study. Lipase activity (hydrolysis of p-nitrophenylbutyrate was measured in the gastrointestinal tract at the end of the study and the contents of CA, carnosol and methyl carnosate were also determined. Sub-chronic administration of RE moderately reduced body weight gain in both lean and obese animals but did not affect food intake. Serum triglycerides, cholesterol and insulin levels were also markedly decreased in the lean animals supplemented with RE. Importantly, lipase activity was significantly inhibited in the stomach of the RE-supplemented animals where the highest content of intact CA and carnosol was detected. CONCLUSIONS: Our results confirm that long-term administration of RE enriched in CA moderates weight gain and improves the plasma lipids profile, primarily in the lean animals. Our data also suggest that these effects may be caused, at least in part, by a significant inhibition of gastric lipase and subsequent reduction in fat absorption.

Inhibition of Gastric Lipase as a Mechanism for Body Weight and Plasma Lipids Reduction in Zucker Rats Fed a Rosemary Extract Rich in Carnosic Acid

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Romo Vaquero, María; Yáñez-Gascón, María-Josefa; García Villalba, Rocío; Larrosa, Mar; Fromentin, Emilie; Ibarra, Alvin; Roller, Marc; Tomás-Barberán, Francisco; Espín de Gea, Juan Carlos; García-Conesa, María-Teresa

2012-01-01

Background Rosemary (Rosmarinus officinalis L.) extracts (REs) exhibit hepatoprotective, anti-obesity and anti-inflammatory properties and are widely used in the food industry. REs are rich in carnosic acid (CA) and carnosol which may be responsible for some of the biological activities of REs. The aim of this study was to investigate whether inhibition of lipase activity in the gut may be a mechanism by which a RE enriched in CA (40%) modulates body weight and lipids levels in a rat model of metabolic disorders and obesity. Methods and Principal Findings RE was administered for 64 days to lean (fa/+) and obese (fa/fa) female Zucker rats and body weight, food intake, feces weight and blood biochemical parameters were monitored throughout the study. Lipase activity (hydrolysis of p-nitrophenylbutyrate) was measured in the gastrointestinal tract at the end of the study and the contents of CA, carnosol and methyl carnosate were also determined. Sub-chronic administration of RE moderately reduced body weight gain in both lean and obese animals but did not affect food intake. Serum triglycerides, cholesterol and insulin levels were also markedly decreased in the lean animals supplemented with RE. Importantly, lipase activity was significantly inhibited in the stomach of the RE-supplemented animals where the highest content of intact CA and carnosol was detected. Conclusions Our results confirm that long-term administration of RE enriched in CA moderates weight gain and improves the plasma lipids profile, primarily in the lean animals. Our data also suggest that these effects may be caused, at least in part, by a significant inhibition of gastric lipase and subsequent reduction in fat absorption. PMID:22745826

Serum Lipase as Clinical Laboratory Index for Chronic Renal Failure Diagnosis.

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Zhu, Ying; Dong, Jing; Wang, Ping; Huang, Huifang; Jin, Xiaohua; Zhou, Jingou; Shi, Jingfang; Gu, Guohao; Chen, Jun; Xu, Jun; Song, Yanhui

2016-07-01

Measuring the level of serum lipase has been used for the clinical diagnosis of acute pancreatitis. Reports showed that the serum lipase level increased in patients of clinical renal failure. In this study, we aimed to measure the change of serum lipase levels in chronic kidney diseases and determine whether it could serve as a clinical laboratory index for clinical renal failure diagnosis. Materials: The OLYMPUS AU5400 automatic biochemical analyzer was used to determine the serum levels of lipase and creatinine. The study included 120 cases in the clinical renal failure group, 76 cases in the nephrotic syndrome group, 81 cases in the chronic nephritis group, and 80 healthy controls from our hospital volunteers in the same period. We then compared the lipase levels and conducted statistical analyses among these groups. The serum lipase levels were 15.3 U/L, 79.8 U/L, 45.1 U/L, and 51.0 U/L in the normal control, clinical renal failure, nephrotic syndrome, and chronic nephritis groups, respectively. The lipase levels in the groups with diseases were significantly different compared with that of the normal control group (p renal failure group was significantly higher than that of the nephrotic syndrome group and chronic nephritis group (p chronic nephritis group (p > 0.05) was observed. Moreover, an association of the serum lipase with disease progression was observed in the study. Serum lipase is an effective serological index which can reflect the clinical changes in the clinical renal failure and tends to increase through the progression of renal dysfunction.

Enhancement of lipase catalyzed-fatty acid methyl esters production from waste activated bleaching earth by nullification of lipase inhibitors.

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Dwiarti, Lies; Ali, Ehsan; Park, Enoch Y

2010-01-01

This study sought to identify inhibitory factors of lipase catalyzed-fatty acid methyl esters (FAME) production from waste activated bleaching earth (wABE). During the vegetable oil refinery process, activated bleaching earth (ABE) is used for removing the impure compounds, but adsorbs vegetable oil up to 35-40% as on a weight basis, and then the wABE is discarded as waste material. The impurities were extracted from the wABE with methanol and evaluated by infra-red (IR) spectroscopy, which revealed that some were chlorophyll-plant pigments. The chlorophylls inhibited the lipase during FAME conversion from wABE. The inhibition by a mixture of chlorophyll a and b was found to be competitive. The inhibition of the enzymatic hydrolysis of waste vegetable oil contained in wABE by chlorophyll a alone was competitive, while the inhibition by chlorophyll b alone was non-competitive. Furthermore, the addition of a small amount of alkali nullified this inhibitory effect and accelerated the FAME production rate. When 0.9% KOH (w/w wABE) was added to the transesterification reaction with only 0.05% lipase (w/w wABE), the maximum FAME production rate improved 120-fold, as compared to that without the addition of KOH. The alkali-combined lipase significantly enhanced the FAME production rate from wABE, in spite of the presence of the plant pigments, and even when a lower amount of lipase was used as a catalyst.

Lipase catalyzed ester synthesis for food processing industries

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Aravindan Rajendran

2009-02-01

Full Text Available Lipases are one of the most important industrial biocatalyst which catalyzes the hydrolysis of lipids. It can also reverse the reaction at minimum water activity. Because of this pliable nature, it is widely exploited to catalyze the diverse bioconversion reactions, such as hydrolysis, esterification, interesterification, alcoholysis, acidolysis and aminolysis. The property to synthesize the esters from the fatty acids and glycerol promotes its use in various ester synthesis. The esters synthesized by lipase finds applications in numerous fields such as biodiesel production, resolution of the recemic drugs, fat and lipid modification, flavour synthesis, synthesis of enantiopure pharmaceuticals and nutraceuticals. It plays a crucial role in the food processing industries since the process is unaffected by the unwanted side products. Lipase modifications such as the surfactant coating, molecular imprinting to suit for the non-aqueous ester synthesis have also been reported. This review deals with lipase catalyzed ester synthesis, esterification strategies, optimum conditions and their applications in food processing industries.Lipases são catalizadores industriais dos mais importantes, os quais catalizam a hidrólise de lipídeos. Também podem reverter a reação a um mínimo de atividade de água. Devido sua natureza flexível, é amplamente explorada para catalizar uma diversidade de reações de bioconversão como hidrólise, esterificação, interesterificação, alcoólise, acidólise e aminólise. A propriedade de síntese de esteres a partir de ácidos graxos e glicerol promoveu seu uso em várias sínteses de esteres. Os esteres sintetizados por lipases encontram aplicação em numerosos campos como a produção de biodiesel, resolução de drogas racêmicas, modificação de gorduras e lipídios, sintese de aromas, síntese de produtos farmacêuticos enantiopuro e nutracêuticos. As lipases possuem um papel crucial nas indústrias de

Biotin-dependent functions in adiposity: a study of monozygotic twin pairs.

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Järvinen, E; Ismail, K; Muniandy, M; Bogl, L H; Heinonen, S; Tummers, M; Miettinen, S; Kaprio, J; Rissanen, A; Ollikainen, M; Pietiläinen, K H

2016-05-01

Biotin acts as a coenzyme for carboxylases regulating lipid and amino-acid metabolism. We investigated alterations of the biotin-dependent functions in obesity and the downstream effects of biotin restriction in adipocytes in vitro. Twenty-four monozygotic twin pairs discordant for body mass index (BMI). Mean within-pair difference (heavy-lean co-twin, Δ) of BMI was 6.0 kg m(-2) (range 3.1-15.2 kg m(-)(2)). Adipose tissue (AT) DNA methylation, gene expression of AT and adipocytes, and leukocytes (real-time quantitative PCR), serum biotin, C-reactive protein (CRP) and triglycerides were measured in the twins. Human adipocytes were cultured in low and control biotin concentrations and analyzed for lipid droplet content, mitochondrial morphology and mitochondrial respiration. The gene expression levels of carboxylases, PCCB and MCCC1, were upregulated in the heavier co-twins' leukocytes. ΔPCCB (r=0.91, P=0.0046) and ΔMCCC1 (r=0.79, P=0.036) correlated with ΔCRP within-pairs. Serum biotin levels were lower in the heavier (274 ng l(-1)) than in the lean co-twins (390 ng l(-1), P=0.034). ΔBiotin correlated negatively with Δtriglycerides (r=-0.56, P=0.045) within-pairs. In AT, HLCS and ACACB were hypermethylated and biotin cycle genes HLCS and BTD were downregulated (PBiotin-dependent carboxylases were downregulated (ACACA, ACACB, PCCB, MCCC2 and PC; Pbiotin had decreased lipid accumulation, altered mitochondrial morphology and deficient mitochondrial respiration. Biotin-dependent functions are modified by adiposity independent of genetic effects, and correlate with inflammation and hypertriglyceridemia. Biotin restriction decreases lipid accumulation and respiration, and alters mitochondrial morphology in adipocytes.

Glycerol Monolaurate Inhibits Lipase Production by Clinical Ocular Isolates Without Affecting Bacterial Cell Viability.

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Flanagan, Judith Louise; Khandekar, Neeta; Zhu, Hua; Watanabe, Keizo; Markoulli, Maria; Flanagan, John Terence; Papas, Eric

2016-02-01

We sought to determine the relative lipase production of a range of ocular bacterial isolates and to assess the efficacy of glycerol monolaurate (GML) in inhibiting this lipase production in high lipase-producing bacteria without affecting bacterial cell growth. Staphylococcus aureus,Staphylococcus epidermidis,Propionibacterium acnes, and Corynebacterium spp. were inoculated at a density of 10(6)/mL in varying concentrations of GML up to 25 μg/mL for 24 hours at 37 °C with constant shaking. Bacterial suspensions were centrifuged, bacterial cell density was determined, and production of bacterial lipase was quantified using a commercial lipase assay kit. Staphylococcus spp. produced high levels of lipase activity compared with P. acnes and Corynebacterium spp. GML inhibited lipase production by Staphylococcal spp. in a dose-dependent manner, with S. epidermidis lipase production consistently more sensitive to GML than S. aureus. Glycerol monolaurate showed significant (P < 0.05) lipase inhibition above concentrations of 15 μg/mL in S. aureus and was not cytotoxic up to 25 μg/mL. For S. epidermidis, GML showed significant (P < 0.05) lipase inhibition above 7.5 μg/mL. Lipase activity varied between species and between strains. Staphylococcal spp. produced higher lipase activity compared with P. acnes and Corynebacterium spp. Glycerol monolaurate inhibited lipase production by S. aureus and S. epidermidis at concentrations that did not adversely affect bacterial cell growth. GML can be used to inhibit ocular bacterial lipase production without proving detrimental to commensal bacteria viability.

Dietary fatty acids early in life affect lipid metabolism and adiposity in young rats.

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Silva, Ana Paula S; Guimarães, Daniella E D; Mizurini, Daniella M; Maia, Ingrid C; Ortiz-Costa, Susana; Sardinha, Fátima L; do Carmo, Maria G Tavares

2006-06-01

The purpose of this study was to evaluate the effects of four isoenergetic diets of differing fat composition on blood lipid profile and adiposity in young rats. Diets containing different lipid sources--partially hydrogenated vegetable oil (PHVO), palm oil (PO), canola oil (CO), and soy oil (SO)--were fed to lactating rats during the 21 days of lactation, and then fed to young males following weaning until the 45th day of life. In vivo lipogenesis rate (LR), lipid content (LC), relative level of FA, and the activity of lipoprotein lipase (LPL) enzyme were measured in epididymal adipose tissue (EPI). Fasting blood lipoproteins and LC in the carcass were also appraised. Body weight of PO and PHVO groups was significantly higher than CO and SO groups from day 14 of lactation to day 45, despite the lower food intake in the PHVO group. PO and PHVO groups presented higher LR and LC in EPI than SO and CO groups. Carcass fat content was significantly higher in PHVO and PO groups than in CO and SO groups. The LPL activity in EPI was unaffected by dietary lipids. PHVO group had increased total cholesterol and TAG concentrations in comparison with the PO group, and significantly lower HDL level compared with the other groups. These results show that the kind of FA in the dietary lipid offered early in life can affect lipid metabolism and adiposity.

Cholesterol efflux from THP-1 macrophages is impaired by the fatty acid component from lipoprotein hydrolysis by lipoprotein lipase

International Nuclear Information System (INIS)

Yang, Yanbo; Thyagarajan, Narmadaa; Coady, Breanne M.; Brown, Robert J.

2014-01-01

Highlights: • Lipoprotein hydrolysis products were produced by lipoprotein lipase. • Hydrolysis products lowers expression of macrophage cholesterol transporters. • Hydrolysis products reduces expression of select nuclear receptors. • Fatty acid products lowers cholesterol transporters and select nuclear receptors. • Fatty acid products reduces cholesterol efflux from macrophages. - Abstract: Lipoprotein lipase (LPL) is an extracellular lipase that primarily hydrolyzes triglycerides within circulating lipoproteins. Macrophage LPL contributes to atherogenesis, but the mechanisms behind it are poorly understood. We hypothesized that the products of lipoprotein hydrolysis generated by LPL promote atherogenesis by inhibiting the cholesterol efflux ability by macrophages. To test this hypothesis, we treated human THP-1 macrophages with total lipoproteins that were hydrolyzed by LPL and we found significantly reduced transcript levels for the cholesterol transporters ATP binding cassette transporter A1 (ABCA1), ABCG1, and scavenger receptor BI. These decreases were likely due to significant reductions for the nuclear receptors liver-X-receptor-α, peroxisome proliferator activated receptor (PPAR)-α, and PPAR-γ. We prepared a mixture of free fatty acids (FFA) that represented the ratios of FFA species within lipoprotein hydrolysis products, and we found that the FFA mixture also significantly reduced cholesterol transporters and nuclear receptors. Finally, we tested the efflux of cholesterol from THP-1 macrophages to apolipoprotein A-I, and we found that the treatment of THP-1 macrophages with the FFA mixture significantly attenuated cholesterol efflux. Overall, these data show that the FFA component of lipoprotein hydrolysis products generated by LPL may promote atherogenesis by inhibiting cholesterol efflux, which partially explains the pro-atherogenic role of macrophage LPL

Cholesterol efflux from THP-1 macrophages is impaired by the fatty acid component from lipoprotein hydrolysis by lipoprotein lipase

Energy Technology Data Exchange (ETDEWEB)

Yang, Yanbo; Thyagarajan, Narmadaa; Coady, Breanne M.; Brown, Robert J., E-mail: rbrown@mun.ca

2014-09-05

Highlights: • Lipoprotein hydrolysis products were produced by lipoprotein lipase. • Hydrolysis products lowers expression of macrophage cholesterol transporters. • Hydrolysis products reduces expression of select nuclear receptors. • Fatty acid products lowers cholesterol transporters and select nuclear receptors. • Fatty acid products reduces cholesterol efflux from macrophages. - Abstract: Lipoprotein lipase (LPL) is an extracellular lipase that primarily hydrolyzes triglycerides within circulating lipoproteins. Macrophage LPL contributes to atherogenesis, but the mechanisms behind it are poorly understood. We hypothesized that the products of lipoprotein hydrolysis generated by LPL promote atherogenesis by inhibiting the cholesterol efflux ability by macrophages. To test this hypothesis, we treated human THP-1 macrophages with total lipoproteins that were hydrolyzed by LPL and we found significantly reduced transcript levels for the cholesterol transporters ATP binding cassette transporter A1 (ABCA1), ABCG1, and scavenger receptor BI. These decreases were likely due to significant reductions for the nuclear receptors liver-X-receptor-α, peroxisome proliferator activated receptor (PPAR)-α, and PPAR-γ. We prepared a mixture of free fatty acids (FFA) that represented the ratios of FFA species within lipoprotein hydrolysis products, and we found that the FFA mixture also significantly reduced cholesterol transporters and nuclear receptors. Finally, we tested the efflux of cholesterol from THP-1 macrophages to apolipoprotein A-I, and we found that the treatment of THP-1 macrophages with the FFA mixture significantly attenuated cholesterol efflux. Overall, these data show that the FFA component of lipoprotein hydrolysis products generated by LPL may promote atherogenesis by inhibiting cholesterol efflux, which partially explains the pro-atherogenic role of macrophage LPL.

Severe hypertriglyceridemia in a patient heterozygous for a lipoprotein lipase gene allele with two novel missense variants.

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Kassner, Ursula; Salewsky, Bastian; Wühle-Demuth, Marion; Szijarto, Istvan Andras; Grenkowitz, Thomas; Binner, Priska; März, Winfried; Steinhagen-Thiessen, Elisabeth; Demuth, Ilja

2015-09-01

Rare monogenic hyperchylomicronemia is caused by loss-of-function mutations in genes involved in the catabolism of triglyceride-rich lipoproteins, including the lipoprotein lipase gene, LPL. Clinical hallmarks of this condition are eruptive xanthomas, recurrent pancreatitis and abdominal pain. Patients with LPL deficiency and severe or recurrent pancreatitis are eligible for the first gene therapy treatment approved by the European Union. Therefore the precise molecular diagnosis of familial hyperchylomicronemia may affect treatment decisions. We present a 57-year-old male patient with excessive hypertriglyceridemia despite intensive lipid-lowering therapy. Abdominal sonography showed signs of chronic pancreatitis. Direct DNA sequencing and cloning revealed two novel missense variants, c.1302A>T and c.1306G>A, in exon 8 of the LPL gene coexisting on the same allele. The variants result in the amino-acid exchanges p.(Lys434Asn) and p.(Gly436Arg). They are located in the carboxy-terminal domain of lipoprotein lipase that interacts with the glycosylphosphatidylinositol-anchored HDL-binding protein (GPIHBP1) and are likely of functional relevance. No further relevant mutations were found by direct sequencing of the genes for APOA5, APOC2, LMF1 and GPIHBP1. We conclude that heterozygosity for damaging mutations of LPL may be sufficient to produce severe hypertriglyceridemia and that chylomicronemia may be transmitted in a dominant manner, at least in some families.

A hepatic amino acid/mTOR/S6K-dependent signalling pathway modulates systemic lipid metabolism via neuronal signals.

Science.gov (United States)

Uno, Kenji; Yamada, Tetsuya; Ishigaki, Yasushi; Imai, Junta; Hasegawa, Yutaka; Sawada, Shojiro; Kaneko, Keizo; Ono, Hiraku; Asano, Tomoichiro; Oka, Yoshitomo; Katagiri, Hideki

2015-08-13

Metabolism is coordinated among tissues and organs via neuronal signals. Levels of circulating amino acids (AAs), which are elevated in obesity, activate the intracellular target of rapamycin complex-1 (mTORC1)/S6kinase (S6K) pathway in the liver. Here we demonstrate that hepatic AA/mTORC1/S6K signalling modulates systemic lipid metabolism via a mechanism involving neuronal inter-tissue communication. Hepatic expression of an AA transporter, SNAT2, activates the mTORC1/S6K pathway, and markedly elevates serum triglycerides (TGs), while downregulating adipose lipoprotein lipase (LPL). Hepatic Rheb or active-S6K expression have similar metabolic effects, whereas hepatic expression of dominant-negative-S6K inhibits TG elevation in SNAT2 mice. Denervation, pharmacological deafferentation and β-blocker administration suppress obesity-related hypertriglyceridemia with adipose LPL upregulation, suggesting that signals are transduced between liver and adipose tissue via a neuronal pathway consisting of afferent vagal and efferent sympathetic nerves. Thus, the neuronal mechanism uncovered here serves to coordinate amino acid and lipid levels and contributes to the development of obesity-related hypertriglyceridemia.

Study the effect of F17S mutation on the chimeric Bacillus thermocatenulatus lipase

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Seyed Hossein Khaleghinejad

2016-06-01

Full Text Available Lipases (triacylglycerol acylhydrolase, EC 3.1.1.3 are one of the highest value commercial enzymes as they have potential applications in biotechnology for detergents, food, pharmaceuticals, leather, textiles, cosmetics, and paper industries; and are currently receiving considerable attention because of their potential applications in biotechnology. Bacillus thermocatenulatus Lipase 2 (BTL2 is one of the most important research targets, because of its potential industrial applications. In this study, the effect of substitution Phe17 with Ser in mutated BTL2 lipase, which 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. Docking results confirmed the mutated lipase to be better than the chimeric lipase. So, cloning was conducted, and the mutated and chimeric btl2 genes were expressed in Escherichia coli, and then the enzymes were purified by anion exchange chromatography. The mutation increased lipase lipolytic activity against most of the applied substrates, with the exception of tributyrin when compared with chimeric lipase. Further, the mutated lipase exhibited higher activity than the chimeric lipase at all temperatures. Optimum pH of the mutated lipase was obtained at pH 9.5, which was more than the chimeric one. Enzyme activity of the mutated lipase in the presence of organic solvents, detergents, and metal ions was also improved than the chimeric lipase.

A lipase with broad temperature range from an alkaliphilic gamma-proteobacterium isolated in Greenland

DEFF Research Database (Denmark)

Schmidt, Mariane; Larsen, Dorte Møller; Stougaard, Peter

2010-01-01

A gamma-proteobacterium related to the genera Alteromonadales and Pseudomonadales , isolated from a cold and alkaline environment in Greenland, has been shown to produce a lipase active between 5 ° C and 80 ° C, with optimal activity at 55 ° C and pH 8. PCR-based screening of genomic DNA from...... the isolated bacterium, followed by genome walking, resulted in two complete open reading frames, which were predicted to encode a lipase and its helper protein, a lipase foldase. The amino acid sequence derived for the lipase showed resemblance to lipases from Pseudomonas , Rhodoferax, Aeromonas and Vibrio...... . The two genes were cloned into different expression systems in E. coli with or without a putative secretion sequence, but despite the fact that both recombinant lipase and lipase foldase were observed on SDS–PAGE, no recombinant lipase activity was detected. Attempts to refold the recombinant lipase...

Desempenho de diferentes lipases imobilizadas na síntese de biodiesel de óleo de palma = Performance of different immobilized lipases in palm oil biodiesel synthesis

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Grazielle dos Santos Silva

2011-04-01

Full Text Available O presente trabalho teve como objetivo determinar as condicoes otimizadas da sintese enzimatica de biodiesel, a partir do oleo de palma e etanol, empregando diferentes lipases imobilizadas (lipase de Pseudomonas fluorescens imobilizada em SiO2-PVA e lipase de Candida antartica imobilizada em resina acrilica - Novozym„µ 435 em meio isento de solvente. Uma matriz de planejamento fatorial foi utilizada para avaliar a influencia da temperatura (42 ¡V 58„aC e a razao molar entre etanol e oleo de palma (6:1 ¡V 18:1 no rendimento detransesterificacao alcancado para cada preparacao de lipase. Os efeitos principais foram ajustados por analise de regressao multipla a modelos lineares e o rendimento maximo foi obtido quando o sistema operacional foi operado a 42„aC com substratos contendo etanol eoleo de palma na razao molar de 18:1. Os modelos matematicos que representam o rendimento global da reacao para cada lipase imobilizada foram considerados adequados para descrever os resultados experimentais.Optimized conditions for palm oil and ethanol enzymatic biodiesel synthesis were determined with different immobilized lipases SiO2-PVA-immobilized lipase from Pseudomonas fluorescens and acrylic resin-immobilized lipase, NovozymR435, from Candida antartica, in solvent-free medium. A full factorial design assessed the influence oftemperature (42 ¡V 58¢XC and ethanol: palm oil (6:1 ¡V 18:1 molar ratio on the transesterification yield. Main effects were adjusted by multiple regression analysis to linear models and the maximum transesterification yield was obtained at 42¢XC and 18:1 ethanol:palm oil molar ratio. Mathematical models featuring total yield for each immobilized lipase were suitable to describe the experimental results.

AKTIVITAS HIDROLISIS ENZIM LIPASE DARI KENTOS KELAPA TERHADAP MINYAK KELAPA Hidrolysis Activity of Lipase Enzyme from Coconut Houstorium for Coconut Oil

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Mohammad Su’i

2012-05-01

Full Text Available This research was aimed to study hydrolysis conditions of houstorium lipases enzyme using coconut oil as substrate. Hydrolysis conditions studied were substrate (coconut oil concentration, enzyme substrate ratio, duration of hydro- lysis and effect of stirring to hydrolysis. The results show  that lipase of coconut houstorium may be optimally used at a coconut oil concentration of 10 %, enzyme to substrate ratio of 3 : 10 (v/v and hydrolysis for 60 minutes with stirring. ABSTRAK Penelitian ini mempelajari kondisi hidrolisis minyak kelapa yang optimum menggunakan enzim lipase dari kentos kelapa. Kondisi hidrolisis yang dipelajari meliputi konsentrasi substrat optium, perbandingan enzim : substrat dan lama hidrolisis yang optimum serta pengaruh pengadukan selama hidrolisis. Hasil penelitian menunjukkan bahwa, hidrolisis minyak kelapa menggunakan enzim lipase kentos kelapa menghasilkan asam lemak bebas paling banyak pada kon- sentrasi substrat (minyak kelapa 10 %, perbandingan enzim : substrat yaitu 3 : 10 (v/v, lama hidroloisa 60 menit dan dilakukan pengadukan selama hidrolisis.

Streptomyces rimosus GDS(L Lipase: Production, Heterologous Overexpression and Structure-Stability Relationship

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Marija Abramić

2003-01-01

Full Text Available Streptomyces rimosus lipase gene has been overexpressed in a heterologous host, S. lividans TK23. The maximal lipase activity was determined in the culture filtrates of the late stationary phase. Time course of lipase production was monitored by a modified plate assay. S. rimosus lipase gene has been located on the AseI B fragment approximately 2 Mb far from the left end of the S. rimosus linear chromosome. Out of eight examined streptomycetes, the presence of this rare type of bacterial lipase gene was detected in two belonging to the S. rimosus taxonomic cluster, and in one non-related species. Comparison of protein sequences of the Streptomyces lipolytic enzymes was performed. The result indicated the best structural stability of the putative S. coelicolor lipase-2.

A Quantitative Fluorescence-Based Lipase Assay

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Giovanna Lomolino

2012-01-01

Full Text Available An easy and fast gel diffusion assay for detecting and monitoring lipase activity by quantification of fluorescein is described. By measuring the intensity of fluorescein, it is possible to obtain a calibration curve with a regression coefficient better than by using the radius of fluorescent haloes. Through the quantification of fluorescence intensity of fluorescein released after the hydrolysis of a fluorescent ester, fluorescein dibutyrate, used as substrate in agar plates, commercial and skimmed milk lipase activity were studied. Moreover, with this method, lipase activity can be monitored in reaction medium that contains compounds which are affected by turbidity or cause measurement interference for UV-spectrophotometer and fluorimeter. In this experiment, boiled skimmed milk was dispersed in the agar gel with fluorescein dibutyrate, and it was used as a reaction medium to mimic natural conditions. The development of such an assay has a potential for applications in industries ranging from pharmaceuticals to food production and monitoring.

Gamma-irradiation sterilization of lipases for cheese making

Energy Technology Data Exchange (ETDEWEB)

Umanskij, M S; Borovkova, Yu A; Odegov, N I [Vsesoyuznyj Nauchno-Issledovatel' skij Inst. Maslodel' noj i Syrodel' noj Promyshlennosti, Uglich (USSR)

1979-03-01

The possibility of sterilizing the enzyme compounds of lipases from Oospora fragrans strains by gamma irradiation was studied. The enzyme compounds were exposed to gamma irradiation at the doses from 0.1 to 0.8 Mrad with the discreteness of 0.1 Mrad and at the dose of 2.0 Mrad. After the radiation treatment the lipases were investigated for bacterial invasion by the cultivation method and for the lipolytic activity by the titrometrical method. It is shown that the sterilization effect is achieved without losses of lipase activity and the radiation dose necessary for sterilization depends on initial invasion levels in the enzyme compounds.

Selection and optimization of extracellular lipase production using ...

African Journals Online (AJOL)

The aim of this study was to isolate and select lipase-producing microorganisms originated from different substrates, as well as to optimize the production of microbial lipase by submerged fermentation under different nutrient conditions. Of the 40 microorganisms isolated, 39 showed a halo around the colonies and 4 were ...

Adipose tissue redistribution caused by an early consumption of a high sucrose diet in a rat model.

Science.gov (United States)

Castellanos Jankiewicz, Ashley Kate; Rodríguez Peredo, Sofía Montserrat; Cardoso Saldaña, Guillermo; Díaz Díaz, Eulises; Tejero Barrera, María Elizabeth; del Bosque Plata, Laura; Carbó Zabala, Roxana

2015-06-01

Obesity is a major public health problem worldwide. The quantity and site of accumulation of adipose tissue is of great importance for the physiopathology of this disease. The aim of this study was to assess the effect of a high carbohydrate diet on adipose tissue distribution. Male Wistar rats, control (CONT) and high sucrose diet (HSD; 30% sucrose in their drinking water), were monitored during 24 weeks and total energy and macronutrient intake were estimated by measuring daily average consumption. A bioelectrical impedance procedure was performed at 22 weeks of treatment to assess body compartments and systolic arterial blood pressure was measured. Serum was obtained and retroperitoneal adipose tissue was collected and weighed. HSD ingested less pellets and beverage, consuming less lipids and proteins than CONT, but the same amount of carbohydrates. Retroperitoneal adipose tissue was more abundant in HSD. Both groups were normoglycemic; triglycerides, adiponectin and leptin levels were higher, while total cholesterol and HDL-cholesterol were lower in HSD; insulin, HOMA index and systolic blood pressure had a tendency of being higher in HSD. This model presents dyslipidemia and a strong tendency for insulin resistance and hypertension. Even though there was no difference in body compartments between groups, retroperitoneal adipose tissue was significantly increased in HSD. This suggests that a rearrangement of adipose tissue distribution towards the abdominal cavity takes place as a result of chronic high sucrose consumption, which contributes to a higher risk of suffering from metabolic and chronic degenerative diseases. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Optimization of lipase production by Staphylococcus sp. Lp12

African Journals Online (AJOL)

USER

2010-02-08

Feb 8, 2010 ... an enormous attention because of their biotechnological applications. Lipases remain ... selective transformations. The exponential increase in .... mass) lipase production and pH at regular intervals of time 24, 48 and 72 h on ...

Triglycerides and Heart Disease, Still a Hypothesis?

Science.gov (United States)

Goldberg, Ira J.; Eckel, Robert H.; McPherson, Ruth

2011-01-01

The purpose of this article is to review the basic and clinical science relating plasma triglycerides and cardiovascular disease. Although many aspects of the basic physiology of triglyceride production, its plasma transport and tissue uptake have been known for several decades, the relationship of plasma triglyceride levels to vascular disease is uncertain. Are triglyceride rich lipoproteins, their influence on HDL and LDL, or the underlying diseases leading to defects in triglyceride metabolism the culprit? Animal models have failed to confirm that anything other than early fatty lesions can be produced by triglyceride-rich lipoproteins. Metabolic products of triglyceride metabolism can be toxic to arterial cells; however, these studies are primarily in vitro. Correlative studies of fasting and postprandial triglycerides and genetic diseases implicate VLDL and their remnants, and chylomicron remnants in atherosclerosis development; but the concomitant alterations in other lipoproteins and other risk factors obscure any conclusions about direct relationships between disease and triglycerides. Genes that regulate triglyceride levels also correlate with vascular disease. Human intervention trials, however, have lacked an appropriately defined population, and have produced outcomes without definitive conclusions. The time is more than ripe for new and creative approaches to understanding the relationship of triglycerides and heart disease. PMID:21527746

New lipases by mining of Pleurotus ostreatus genome.

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Alessandra Piscitelli

Full Text Available The analysis of Pleurotus ostreatus genome reveals the presence of automatically annotated 53 lipase and 34 carboxylesterase putative coding-genes. Since no biochemical or physiological data are available so far, a functional approach was applied to identify lipases from P. ostreatus. In the tested growth conditions, four lipases were found expressed, with different patterns depending on the used C source. Two of the four identified proteins (PleoLip241 and PleoLip369, expressed in both analysed conditions, were chosen for further studies, such as an in silico analysis and their molecular characterization. To overcome limits linked to native production, a recombinant expression approach in the yeast Pichia pastoris was applied. Different expression levels were obtained: PleoLip241 reached a maximum activity of 4000 U/L, whereas PleoLip369 reached a maximum activity of 700 U/L. Despite their sequence similarity, these enzymes exhibited different substrate specificity and diverse stability at pH, temperature, and presence of metals, detergents and organic solvents. The obtained data allowed classifying PleoLip241 as belonging to the "true lipase" family. Indeed, by phylogenetic analysis the two proteins fall in different clusters. PleoLip241 was used to remove the hydrophobic layer from wool surface in order to improve its dyeability. The encouraging results obtained with lipase treated wool led to forecast PleoLip241 applicability in this field.

Maternal exposure to di-(2-ethylhexyl) phthalate exposure deregulates blood pressure, adiposity, cholesterol metabolism and social interaction in mouse offspring.

Science.gov (United States)

Lee, Kuan-I; Chiang, Chin-Wei; Lin, Hui-Ching; Zhao, Jin-Feng; Li, Cheng-Ta; Shyue, Song-Kun; Lee, Tzong-Shyuan

2016-05-01

Long-term exposure to di-(2-ethylhexyl) phthalate (DEHP) is highly associated with carcinogenicity, fetotoxicity, psychological disorders and metabolic diseases, but the detrimental effects and mechanisms are not fully understood. We investigated the effect of exposing mouse mothers to DEHP, and the underlying mechanism, on blood pressure, obesity and cholesterol metabolism as well as psychological and learning behaviors in offspring. Tail-cuff plethysmography was used for blood pressure measurement; Western blot used was for phosphorylation and expression of protein; hematoxylin and eosin staining, Nissl staining and Golgi staining were used for histological examination. The serum levels of cholesterol, triglycerides and glucose were measured by blood biochemical analysis. Hepatic cholesterol and triglyceride levels were assessed by colorimetric assay kits. Offspring behaviors were evaluated by open-field activity, elevated plus maze, social preference test and Morris water maze. Maternal DEHP exposure deregulated the phosphorylation of endothelial nitric oxide synthase and upregulated angiotensin type 1 receptor in offspring, which led to increased blood pressure. It led to obesity in offspring by increasing the size of adipocytes in white adipose tissue and number of adipocytes in brown adipose tissue. It increased the serum level of cholesterol in offspring by decreasing the hepatic capacity for cholesterol clearance. The impaired social interaction ability induced by maternal DEHP exposure might be due to abnormal neuronal development. Collectively, our findings provide new evidence that maternal exposure to DEHP has a lasting effect on the physiological functions of the vascular system, adipose tissue and nerve system in offspring.

High cell density fed-batch fermentations for lipase production: feeding strategies and oxygen transfer.

Science.gov (United States)

Salehmin, M N I; Annuar, M S M; Chisti, Y

2013-11-01

This review is focused on the production of microbial lipases by high cell density fermentation. Lipases are among the most widely used of the enzyme catalysts. Although lipases are produced by animals and plants, industrial lipases are sourced almost exclusively from microorganisms. Many of the commercial lipases are produced using recombinant species. Microbial lipases are mostly produced by batch and fed-batch fermentation. Lipases are generally secreted by the cell into the extracellular environment. Thus, a crude preparation of lipases can be obtained by removing the microbial cells from the fermentation broth. This crude cell-free broth may be further concentrated and used as is, or lipases may be purified from it to various levels. For many large volume applications, lipases must be produced at extremely low cost. High cell density fermentation is a promising method for low-cost production: it allows a high concentration of the biomass and the enzyme to be attained rapidly and this eases the downstream recovery of the enzyme. High density fermentation enhances enzyme productivity compared with the traditional submerged culture batch fermentation. In production of enzymes, a high cell density is generally achieved through fed-batch operation, not through perfusion culture which is cumbersome. The feeding strategies used in fed-batch fermentations for producing lipases and the implications of these strategies are discussed. Most lipase-producing microbial fermentations require oxygen. Oxygen transfer in such fermentations is discussed.

CE: Triglycerides: Do They Matter?

Science.gov (United States)

Scordo, Kristine; Pickett, Kim Anne

2017-01-01

: Since the introduction of HMG-CoA reductase inhibitors, also known as statins, as an adjunct to diet in the treatment of hyperlipidemia and the greater emphasis placed on reducing low-density lipoprotein (LDL) cholesterol levels in the prevention of atherosclerosis and cardiovascular disease (CVD), there has been less focus on the value of lowering serum triglyceride levels. Many patients are aware of their "good" and "bad" cholesterol levels, but they may not be aware of their triglyceride level or of the association between high triglycerides and the development of CVD. In recent years, however, in light of the increasing incidences of obesity, insulin resistance, and type 2 diabetes, lowering triglyceride levels has gained renewed interest. In addition to the focus on lowering LDL cholesterol levels in CVD prevention, clinicians need to be aware of the role of triglycerides-their contribution to CVD, and the causes and treatment of hypertriglyceridemia.

Lipase polystyrene giant amphiphiles.

Science.gov (United States)

Velonia, Kelly; Rowan, Alan E; Nolte, Roeland J M

2002-04-24

A new type of giant amphiphilic molecule has been synthesized by covalently connecting a lipase enzyme headgroup to a maleimide-functionalized polystyrene tail (40 repeat units). The resulting biohybrid forms catalytic micellar rods in water.

Plant latex lipase as biocatalysts for biodiesel production | Mazou ...

African Journals Online (AJOL)

Plant latex lipase as biocatalysts for biodiesel production. ... This paper provides an overview regarding the main aspects of latex, such as the reactions catalyzed, physiological functions, specificities, sources and their industrial applications. Keywords: Plant latex, lipase, Transesterification, purification, biodiesel ...

Isolation and characterization of lipase-producing Bacillus strains ...

African Journals Online (AJOL)

Bacillus strains (B1 - B5) producing extra cellular lipase were isolated from the soil sample of coconut oil industry. The strains were identified by morphological and biochemical characters. Growth of the organisms and lipase production were measured with varying pH (4 - 9) temperature (27, 37 and 47ºC) and various ...

Production of extracellular lipase by the phytopathogenic fungus Fusarium solani FS1 Produção de lipase extracelular pelo fungo fitopatogênico Fusarium solani FS1

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Maria de Mascena Diniz Maia

1999-12-01

Full Text Available A Brazilian strain of Fusarium solani was tested for extracellular lipase production in peptone-olive oil medium. The fungus produced 10,500 U.l-1 of lipase after 72 hours of cultivation at 25oC in shake-flask at 120 rpm in a medium containing 3% (w/v peptone plus 0.5% (v/v olive oil. Glucose (1% w/v was found to inhibit the inductive effect of olive oil. Peptone concentrations below 3% (w/v resulted in a reduced lipase production while increased olive oil concentration (above 0.5% did not further stimulate lipase production. The optimum lipase activity was achieved at pH 8.6 and 30oC and a good enzyme stability (80% activity retention was observed at pH ranging from 7.6 to 8.6, and the activity rapidly dropped at temperatures above 50oC. Lipase activity was stimulated by the addition of n-hexane to the culture medium supernatants, in contrast to incubation with water-soluble solvents.

Nordihydroguaiaretic acid protects against high-fat diet-induced fatty liver by activating AMP-activated protein kinase in obese mice

Energy Technology Data Exchange (ETDEWEB)

Lee, Myoung-Su; Kim, Daeyoung; Jo, Keunae [Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 262 Seongsanno, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Hwang, Jae-Kwan, E-mail: jkhwang@yonsei.ac.kr [Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 262 Seongsanno, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Translational Research Center for Protein Function Control, Yonsei University, 262 Seongsanno, Seodaemun-gu, Seoul 120-749 (Korea, Republic of)

2010-10-08

Research highlights: {yields} NDGA decreases high-fat diet-induced body weight gain and adiposity. {yields} NDGA reduces high-fat diet-induced triglyceride accumulation in liver. {yields} NDGA improves lipid storage in vitro through altering lipid regulatory proteins. {yields} Inhibition of lipid storage in vivo and in vitro is mediated by AMPK activation. -- Abstract: Nonalcoholic fatty liver disease, one of the most common causes of chronic liver disease, is strongly associated with metabolic syndrome. Nordihydroguaiaretic acid (NDGA) has been reported to inhibit lipoprotein lipase; however, the effect of NDGA on hepatic lipid metabolism remains unclear. We evaluated body weight, adiposity, liver histology, and hepatic triglyceride content in high-fat diet (HFD)-fed C57BL/6J mice treated with NDGA. In addition, we characterized the underlying mechanism of NDGA's effects in HepG2 hepatocytes by Western blot and RT-PCR analysis. NDGA (100 or 200 mg/kg/day) reduced weight gain, fat pad mass, and hepatic triglyceride accumulation, and improved serum lipid parameters in mice fed a HFD for 8 weeks. NDGA significantly increased AMP-activated protein kinase (AMPK) phosphorylation in the liver and in HepG2 hepatocytes. NDGA downregulated the level of mature SREBP-1 and its target genes (acetyl-CoA carboxylase and fatty acid synthase), but, it upregulated expression of genes involved in fatty acid oxidation, such as peroxisome proliferator-activated receptor (PPAR){alpha}, PPAR{gamma} coactivator-1, carnitine palmitoyl transferase-1, and uncoupling protein-2. The specific AMPK inhibitor compound C attenuated the effects of NDGA on expression of lipid metabolism-related proteins in HepG2 hepatocytes. The beneficial effects of NDGA on HFD-induced hepatic triglyceride accumulation are mediated through AMPK signaling pathways, suggesting a potential target for preventing NAFLD.

Nordihydroguaiaretic acid protects against high-fat diet-induced fatty liver by activating AMP-activated protein kinase in obese mice

International Nuclear Information System (INIS)

Lee, Myoung-Su; Kim, Daeyoung; Jo, Keunae; Hwang, Jae-Kwan

2010-01-01

Research highlights: → NDGA decreases high-fat diet-induced body weight gain and adiposity. → NDGA reduces high-fat diet-induced triglyceride accumulation in liver. → NDGA improves lipid storage in vitro through altering lipid regulatory proteins. → Inhibition of lipid storage in vivo and in vitro is mediated by AMPK activation. -- Abstract: Nonalcoholic fatty liver disease, one of the most common causes of chronic liver disease, is strongly associated with metabolic syndrome. Nordihydroguaiaretic acid (NDGA) has been reported to inhibit lipoprotein lipase; however, the effect of NDGA on hepatic lipid metabolism remains unclear. We evaluated body weight, adiposity, liver histology, and hepatic triglyceride content in high-fat diet (HFD)-fed C57BL/6J mice treated with NDGA. In addition, we characterized the underlying mechanism of NDGA's effects in HepG2 hepatocytes by Western blot and RT-PCR analysis. NDGA (100 or 200 mg/kg/day) reduced weight gain, fat pad mass, and hepatic triglyceride accumulation, and improved serum lipid parameters in mice fed a HFD for 8 weeks. NDGA significantly increased AMP-activated protein kinase (AMPK) phosphorylation in the liver and in HepG2 hepatocytes. NDGA downregulated the level of mature SREBP-1 and its target genes (acetyl-CoA carboxylase and fatty acid synthase), but, it upregulated expression of genes involved in fatty acid oxidation, such as peroxisome proliferator-activated receptor (PPAR)α, PPARγ coactivator-1, carnitine palmitoyl transferase-1, and uncoupling protein-2. The specific AMPK inhibitor compound C attenuated the effects of NDGA on expression of lipid metabolism-related proteins in HepG2 hepatocytes. The beneficial effects of NDGA on HFD-induced hepatic triglyceride accumulation are mediated through AMPK signaling pathways, suggesting a potential target for preventing NAFLD.

Rat liver contains a limited number of binding sites for hepatic lipase

NARCIS (Netherlands)

G.C. Schoonderwoerd (Kees); A.J.M. Verhoeven (Adrie); H. 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

Lipase inhibition and antiobesity effect of Atractylodes lancea.

Science.gov (United States)

Jiao, Ping; Tseng-Crank, Julie; Corneliusen, Brandon; Yimam, Mesfin; Hodges, Mandee; Hong, Mei; Maurseth, Catherine; Oh, Misun; Kim, Hyunjin; Chu, Min; Jia, Qi

2014-05-01

The ethanol extract of Atractylodes lancea rhizome displayed significant lipase inhibition with an IC50 value of 9.06 µg/mL in a human pancreatic lipase assay from high-throughput screening. Bioassay-guided isolation led to the identification of one new polyacetylene, syn-(5E,11E)-3-acetoxy-4-O-(3-methylbutanoyl)-1,5,11-tridecatriene-7,9-diyne-3,4-diol (7), along with six known compounds (1-6). The structure of compound 7 was determined based on the analysis of NMR and MS data. Among these seven lipase inhibitors, the major compound atractylodin (1) showed the highest lipase inhibitory activity (IC50 = 39.12 µM). The antiobesity effect of the ethanol extract of Atractylodes lancea rhizome was evaluated in a high-fat diet-induced obesity mice model at daily dosages of 250 mg/kg and 500 mg/kg body weight for 4 weeks, and treatment with this extract demonstrated a moderate efficacy at the 500 mg/kg dose level. Georg Thieme Verlag KG Stuttgart · New York.

Comparative performance of microbial lipases immobilized on magnetic polysiloxane polyvinyl alcohol particles

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Laura Maria Bruno

2008-10-01

Full Text Available Microbial lipase from Mucor miehei and Candida rugosa were immobilized by covalent binding onto magnetized polysiloxane polyvinyl alcohol particles (POS-PVA. The resulting immobilized derivatives were evaluated in aqueous solution (olive oil hydrolysis and organic solvent (butyl butyrate synthesis. Higher catalytic activities were found when the coupling procedure was made with M. miehei lipase. Immobilized M. miehei lipase also showed a better operational stability and a higher half-life than C. rugosa lipase after the successive batches of esterification. The performance of C. rugosa immobilized derivative was constrained by the low lipase loading used in the immobilizing step. Further information regarding the both immobilized derivatives was also obtained through chemical composition (FTIR.Lipases microbianas de Mucor miehei e Candida rugosa foram imobilizadas por ligação covalente em partículas magnetizadas de polisiloxano-álcool polivinílico (POS-PVA. Os derivados imobilizados resultantes foram avaliados em solução aquosa (hidrólise de azeite de oliva e em solvente orgânico (síntese de butirato de butila. As maiores atividades catalíticas foram encontradas quando o procedimento de ligação foi realizado com lipase de M. miehei. O derivado imobilizado de lipase de M. miehei também apresentou melhores resultados de estabilidade operacional e tempo de meia-vida do que o de lipase de C. rugosa, após sucessivas bateladas de esterificação. O desempenho do derivado imobilizado de C. rugosa foi restringido pelo baixo carregamento de lipase usado na etapa de imobilização. Informações adicionais a respeito de ambos derivados imobilizados também foram obtidas através da composição química (FTIR.

Post-heparin plasma lipoprotein lipase, but not hepatic lipase activity, is related to plasma adiponectin in type 2 diabetic patients and healthy subjects

NARCIS (Netherlands)

De Vries, R; Wolffenbuttel, BHR; Sluiter, WJ; Van Tol, A; Dullaart, RPF

2005-01-01

The aim of this study was to determine the relationships of plasma adiponectin with post-heparin plasma lipoprotein lipase (LPL) and hepatic lipase (HL) activities, and to evaluate whether plasma adiponectin contributes to diabetes-associated dyslipidaemia. Plasma adiponectin, post-heparin plasma

SUITABILITY OF VISCERAL ADIPOSITY INDEX AS A MARKER FOR CARDIOMETABOLIC RISKS IN JORDANIAN ADULTS.

Science.gov (United States)

Numan Ahmad, Mousa; Halim Haddad, Fares

2015-12-01

visceral adiposity index (VAI) has recently been proposed as a predictor of cardiometabolic risk, but its usefulness has not been confirmed. to evaluate the association between VAI and conventional adiposity and cardiometabolic risk indices and examine VAI risk predictive ability and compare it with other adiposity indices. a total of 1 622 Jordanian adults, 686 men and 936 women, aged 20-80 years were included this study. VAI, body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), waist-height ratio (WHtR) were examined and high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), fasting serum glucose (FSG), systolic (SBP), and diastolic (DBP) blood pressure were determined. Associations and age-and gender specific distribution and differences were evaluated. Receiver operating characteristic (ROC) curve and area under curve (AUC) were used for risk predictive ability comparison. VAI of women (6.82±6.43) was higher than of men (4.15±4.62). VAI severity increased with age in a dose-response trend (padiposity and cardiometabolic indices. VAI markedly associated with TG, HDL-C, FSG, SBP and DBP or WHR, WC, WHtR and BMI in respective order of correlation potency for cardiometabolic or adiposity risk indices. In men and women respectively, the largest AUC was for VAI (0.79 vs. 0.77), followed by WHR (0.73 vs. 0.75), WC (0.69 vs. 0.74), WHtR (0.65 vs. 0.71) and BMI (0.53 vs. 0.51). the findings suggest that VAI potentially associates with cardiometabolic risks and proves to be superior to other adiposity indices in predicting such risk. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Lipases de látex vegetais: propriedades e aplicações industriais

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Paques Fernanda Wiermann

2006-01-01

Full Text Available Biocatalysts have innumerous advantages with respect to classical chemical processes, such as high specificity. Lipases (EC 3.1.1.3 are biocatalysts with large application in synthesis and hydrolysis reactions of triacylglycerols. The search for new sources of lipases has been intensified in the last years due to the high cost of microbial and animal lipases, wich restricts their use on an industrial scale. Lipases obtained from the latex of Carica papaya, Carica pentagona, Euphorbia characias, E. wulfenii, known for their proteolytic properties, are a good alternative source. In this review, we describe the well-known sources of vegetal lipases extracted from the latex and present some of their industrial applications.

Structural investigations of the regio- and enantioselectivity of lipases

NARCIS (Netherlands)

Lang, Dietmar A.; Dijkstra, Bauke W.

Although lipases are widely applied for the stereospecific resolution of racemic mixtures of esters, the atomic details of the factors that are responsible for their stereospecificity are largely obscure. We determined the X-ray structures of Pseudomonas cepacia lipase in complex with two

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-Sepharos...

Purification and Characterization of Lipase from Aspergillus flavus ...

African Journals Online (AJOL)

USER

Abstract. Lipase from Aspergillus flavus was purified in a single step purification using MnFeO4 magnetic nano particles to achieve a 20.53- fold purification with specific activity of. 11.29 U/mg and a 59% recovery yield. SDS-PAGE of lipase showed a single pure band with corresponding molecular weight of 35 kDa.

Purification and Characterization of Lipase from Aspergillus flavus ...