bluuebunny/crossref_metadata_2025_split huggingface dataset:
Postprandial triglyceride‐rich lipoprotein metabolism and insulin sensitivity in nonalcoholic steatohepatitis patients
Authors: Cassader Maurizio , Gambino Roberto , Musso Giovanni , Depetris Nadia , Mecca Fabio , Cavallo‐Perin Paolo , Pacini Giovanni , Rizzetto Mario , Pagano Gianfranco 
Published: November 2006

AbstractNonalcoholic steatohepatitis (NASH) is a syndrome frequently associated with obesity, diabetes mellitus, and dyslipidemia. Increased fasting insulinemia and blood glucose levels may trigger a reduced catabolism of lipoproteins rich in triglycerides by lipoprotein lipase (LPL) and an increase in their fasting and postprandial levels. An association between postprandial lipemia and coronary heart disease has been observed, and many studies now support this concept. The most important result of our study is the increase in triglyceride‐rich lipoproteins response after a fat load in NASH patients, the increase of incremental area under the postprandial curve, and the duration of the hypertriglyceridemic peaks. The persisting postprandial plasma triglyceride elevation in NASH patients was mostly due to the elevated plasma level of large triglyceride‐rich particles. These data are coupled with lower plasma HDL2‐cholesterol levels. As for lipoprotein analyses, the number of apolipoprotein B100 (ApoB100) particles is not significantly different between the two groups, and the higher content of triglycerides in NASH very low density lipoproteins (VLDL) increases the triglyceride‐to‐ApoB ratio and the particle size. A decreased enzymatic activity of LPL or a defective assembly and secretion of VLDL from hepatocytes due to a moderate reduction in microsomal triglyceride transfer protein could be involved in the overloading of VLDL. Moreover, the undetectable levels of ApoB48 in triglyceride‐rich lipoproteins fraction A could be related to the synthesis of smaller and denser chylomicrons. NASH patients not only are insulin resistant but also tend to present alterations in fatty meal delivery, suggesting that an increase in fasting plasma insulin and glucose, with insulin resistance, joins with depressed metabolism of triglyceride‐rich lipoproteins. An increase in postprandial triglyceride levels with production of large VLDL suggests an atherogenic behavior of lipid metabolism, in accordance with the high prevalence of the metabolic syndrome in NASH patients. This paper suggests that a fat load may be useful in early detection of atherogenic risk in the presence of otherwise normal fasting plasma lipids.
Arachidyl amido cholanoic acid (aramchol) is a cholesterol solubilizer and prevents the formation of cholesterol gallstones in inbred mice
Authors: Gilat Tuvia , Leikin‐Frenkel Alicia , Goldiner Ilana , Laufer Hava , Halpern Zamir , Konikoff Fred M. 
Published: November 2006

AbstractWe have recently synthesized fatty acid bile acid conjugates (FABAC) that were able to reduce and retard cholesterol crystallization in model and human biles. When given orally, they prevented the formation of cholesterol crystals in the bile of hamsters. The aim of the present study was to determine whether the FABAC are cholesterol solubilizers, whether they can dissolve pre‐existing crystals, whether they can prevent the formation of cholesterol gallstones, and to investigate the optimal type of bond between the fatty acid and bile acid. The presence of cholesterol crystals was determined by light microscopy, and the total crystal mass of precipitated crystals was measured by chemical means. Inbred (C57J/L) mice on a lithogenic diet were used to evaluate cholesterol crystal formation, dissolution, and gallstone formation in vivo. Arachidyl amido cholanoic acid (Aramchol) was the FABAC used in the present experiments. At equimolar amounts, the cholesterol‐solubilizing capacity of Aramchol was higher than that of taurocholate and similar to that of phosphatidylcholine. The addition of Aramchol dissolved approximately 50% of preexisting crystals in model bile solutions. The same phenomenon was demonstrated in human bile ex vivo, with a dose‐response effect. All inbred mice developed cholesterol crystals in bile after 10–14 d on the lithogenic diet. Thereafter, supplementation of the diet with Aramchol progressively reduced the proportion of mice with crystals to 25% after 28 d. On the lithogenic diet, 100% of inbred mice developed cholesterol gallstones in the gallbladder by day 21. None of the mice whose diet was supplemented with 0.5 mg or 1.0 mg of Aramchol/d developed stones or crystals. FABAC are a new class of molecules that are cholesterol solubilizers and which are able to dissolve cholesterol crystals in bile. Upon oral administration, they dissolve pre‐existing cholesterol crystals and prevent the formation of gallstones in gallstone‐susceptible mice.
Alterations in fatty acid composition of tissue phospholipids in the developing retinal dystrophic rat
Authors: Alessandri J. M. , Goustard‐Langelier B. 
Published: November 2006

AbstractAlterations in lipid composition occur in the retinal pigment epithelium and photoreceptor cells of the Royal College of Surgeons (RCS) dystrophic rat, a model for inherited retinal degeneration. With respect to lipid composition of nonretinal tissues, the developmental timing of lipid alterations and the incidence of dystrophy are unknown. We determined the fatty acid composition in choline phosphoglycerides (ChoGpl) and ethanolamine phosphoglycerides (EtnGpl) in the brain, liver, and retina from dystrophic RCS rats and from their nondystrophic congenics (controls) at the ages of 3 and 6 wk. At 3 wk, the fatty acid compositions were specific to individual phospholipid classes without any difference between dystrophic and nondystrophic tissues. In plasma phospholipids, there was an age‐related increase in the relative contents of monounsaturated and n‐3 polyunsaturated fatty acids, with only minor differences between dystrophic and nondystrophic rats. At 6 wk, the fatty acid compositions in ChoGpl and EtnGpl from dystrophic brain and retina were significantly different from those of nondystrophics. The effect of strain on developmental changes in brain fatty acid composition was significant for 18∶0 and 22∶6n−3 in EtnGpl and for 16∶0, 18∶0, 18∶1n−9, and 20∶4n−6 in ChoGpl. The brain ChoGpl fatty acid composition in nondystrophic rats was similar at 6 wk to that of normal rats, and there were almost no postweaning changes in the dystrophics. In retinal phospholipids, the effect of dystrophy was to increase the 20∶4n−6 content in EtnGpl and to decrease 22∶6n−3 in ChoGpl. The 18∶2n−6 and 22∶6n−3 contents in dystrophic liver ChoGpl were also significantly affected, while no difference was observed in the EtnGpl fraction. The dystrophy affected the phospholipid fatty acid developmental changes in a tissue‐ and class‐specific manner. Fatty acid metabolism could be selectively altered in neural and nonneural tissues of developing dystrophic RCS rats.
Biosynthesis and tissue deposition of docosahexaenoic acid (22∶6n−3) in rainbow trout (Oncorhynchus mykiss)
Authors: Bell M. V. , Dick J. R. , Porter A. E. A. 
Published: November 2006

AbstractRainbow trout (Oncorhynchus mykiss) weighing ca. 5 g and previously acclimated for 8 wk on a diet comprising vegetable oil (11%), fish meal (5%), and casein (48%) as the major constituents were fed a pulse of diet containing deuterated (D5) (17,17,18,18,18)‐18∶3n−3 ethyl ester. The synthesis and tissue distribution of D5‐22∶6n−3 was determined 3,7,14, 24, and 35 d after the pulse. The whole‐body accumulation of D5‐22∶6n−3 was linear over the first 7 d, corresponding to a rate of 0.54±0.12 μg D5‐22∶6n−3/g fish/mg D5‐18∶3n−3 eaten/d. Maximal accretion of D5‐22∶6n−3 was 4.3±1.2 μg/g fish/mg of D5‐18∶3n−3 eaten after 14 d. The amount of D5‐22∶6n−3 peaked in liver at day 7, in brain and eyes at day 24, and plateaued after day 14 in visceral and eye socket adipose tissue and in the whole fish. The majority of D5‐22∶6n−3 was found in the carcass (remaining tissues minus the above tissues analyzed separately) at all times. On a per milligram lipid basis, liver and eyes had the highest concentration of D5‐22∶6n−3. The experimental diet also contained 21∶4n−6 ethyl ester as a marker to estimate the amount of food eaten by individual fish. From such estimates it was calculated that the great majority of the D5‐tracer was catabolized, with the combined recovery of D5‐18∶3n−3 plus D5‐22∶6n−3 being 2.6%. The recovery of 21∶4n−6 was 57.6%. The concentration of 22∶6n−3 in the fish decreased during the 13‐wk period, and the amount of 22∶6n−3 synthesized from 18∶3n−3 was only about 5% of that obtained directly from the fish meal in the diet.
An octaethylene glycol monododecyl ether‐based mixed micellar assay for determining the lipid acyl hydrolase activity of patatin
Authors: Jimenez Mercedes , Escribano Josefa , Pérez‐Gilabert Manuela , Chazarra Soledad , Cabanes Juana , García‐Carmona Francisco 
Published: November 2006

AbstractPatatin was extracted from potato tubers (Solanum tuberosum L. cv. Spunta) and purified to homogeneity by ammonium sulfate salt fractionation and one sole chromatographic step. A spectrophotometric mixed micellar assay for patatin lipid acyl hydrolase (LAH) activity was designed with the detergent octaethylene glycol monododecyl ether (C12E8). Patatin LAH used p‐nitrophenyl butyrate (PNP‐butyrate) as substrate when solubilized in (C12E8) micelles. In the mixed micellar system, patatin LAH responds to the PNP‐butyrate surface concentration expressed as mol% (=[PNP‐butyrate]·100/([detergent]‐critical micellar concentration)) and not to the molarity of PNP‐butyrate. The kinetic parameters were determinined; Vmax was independent of the mixed micelle concentration, as was Km, when expressed as mol%. However, Km was dependent on C12E8 concentration when expressed in molar concentration. C12E8/PNP‐butyrate proved to be a reliable system for assaying patatin LAH activity and is superior to the commonly used Triton X‐100 and SDS methods. It permits investigation of the substrate requirements of patatin LAH activity because the concentration‐independent Km can be determined both in mol% and as the absolute number of substrate molecules per micelle. In addition, the detergent did not affect the enzyme activity.
Transforming growth factor beta in human milk does not change in response to modest intakes of docosahexaenoic acid
Authors: Hawkes J. S. , Bryan D‐L. , Neumann M. A. , Makrides M. , Gibson R. A. 
Published: November 2006

AbstractLong‐chain polyunsaturated fatty acids have been associated with aspects of immune regulation including cytokine production. The purpose of this study was to investigate the effect of maternal dietary supplementation with tuna oil, rich in docosahexaenoic acid (DHA), on the concentration of transforming growth factor beta 1 (TGFβ1) and TGFβ2 in breast milk. In this randomized, dietary intervention trial, mothers of term infants consumed a daily supplement of 2000 mg oil containing either placebo (n=40), 300 mg DHA (n=40), or 600 mg DHA (n=40). The DHA increase in milk and plasma was proportional to dietary DHA. There was no relationship between milk DHA status and TGFβ1 and TGFβ2 levels.
Influence of dietary supplementation with long‐chain n−3 or n−6 polyunsaturated fatty acids on blood inflammatory cell populations and functions and on plasma soluble adhesion molecules in healthy adults
Authors: Thies F. , Miles E. A. , Nebe‐von‐Caron G. , Powell J. R. , Hurst T. L. , Newsholme E. A. , Calder P. C. 
Published: November 2006

AbstractGreatly increasing the amounts of flaxseed oil [rich in α‐linolenic acid (ALNA)] or fish oil (FO); [rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] in the diet can decrease inflammatory cell functions and so might impair host defense. The objective of this study was to determine the effect of dietary supplementation with moderate levels of ALNA, γ‐linolenic acid (GLA), arachidonic acid (ARA), DHA, or FO on inflammatory cell numbers and functions and on circulating levels of soluble adhesion molecules. Healthy subjects aged 55 to 75 yr consumed nine capsules per day for 12 wk. The capsules contained placebo oil (an 80∶20 mix of palm and sunflowerseed oils) or blends of placebo oil with oils rich in ALNA, GLA, ARA, or DHA or FO. Subjects in these groups consumed 2 g ALNA; approximately 700 mg GLA, ARA, or DHA; or 1 g EPA plus DHA (720 mg EPA+280 mg DHA) daily from the capsules. Total fat intake from the capsules was 4 g per day. None of the treatments affected inflammatory cell numbers in the bloodstream; neutrophil and monocyte phagocytosis or respiratory burst in response to E. coli; production of tumor necrosis factor‐α, interleukin‐1β, and interleukin‐6 in response to bacterial lipopolysaccharide; or plasma concentrations of soluble intercellular adhesion molecule‐1. In contrast, the ALNA and FO treatments decreased the plasma concentrations of soluble vascular cell adhesion molecule‐1 (16 and 28% decrease, respectively) and soluble E‐selectin (23 and 17% decrease, respectively). It is concluded that, in contrast to previous reports using higher amounts of these fatty acids, a moderate increase in consumption of long‐chain n−6 or n−3 polyunsaturated fatty acids does not significantly affect inflammatory cell numbers or neutrophil and monocyte responses in humans and so would not be expected to cause immune impairment. Furthermore, we conclude that moderate levels of ALNA and FO, which could be incorporated into the diet, can decrease some markers of endothelial activation and that this mechanism of action may contribute to the reported health benefits of n−3 fatty acids.
Effects of dietary virgin olive oil phenols on low density lipoprotein oxidation in hyperlipidemic patients
Authors: Masella Roberta , Giovannini Claudio , Varì Rosaria , Di Benedetto Roberta , Coni Ettore , Volpe Roberto , Fraone Nadia , Bucci Antonello 
Published: November 2006

AbstractThe aim of this study was to assess the effects of the dietary intake of extra virgin olive oil on the oxidative susceptibility of low density lipoproteins (LDL) isolated from the plasma of hyperlipidemic patients. Ten patients with combined hyperlipidemia (mean plasma cholesterol 281 mg/dL, triglycerides 283 mg/dL) consumed a low‐fat, low‐cholesterol diet, with olive oil (20 g/d) as the only added fat, with no drug or vitamin supplementation for 6 wk. Then they were asked to replace the olive oil they usually consumed with extra virgin olive oil for 4 wk. LDL were isolated at the beginning, and after the 4 wk of dietary treatment. LDL susceptibility to CuSO4‐mediated oxidation was evaluated by measuring the extent of lipid peroxidation. We also determined fatty acid composition and vitamin E in plasma and LDL and plasma phenolic content. Extra virgin olive oil intake did not affect fatty acid composition of LDL but significantly reduced the copper‐induced formation of LDL hydroperoxides and lipoperoxidation end products as well as the depletion of LDL linoleic and arachidonic acid. A significant increase in the lag phase of conjugated diene formation was observed after dietary treatment. These differences are statistically correlated with the increase in plasma phenolic content observed at the end of the treatment with extra virgin olive oil; they are not correlated with LDL fatty acid composition or vitamin E content, which both remained unmodified after the added fat change. This report suggests that the daily intake of extra virgin olive oil in hyperlipidemic patients could reduce the susceptibility of LDL to oxidation, not only because of its high monounsaturated fatty acid content but probably also because of the antioxidative activity of its phenolic compounds.
Production of docosahexaenoic acid by Crypthecodinium cohnii grown in a pH‐auxostat culture with acetic acid as principal carbon source
Authors: Ratledge Colin , Kanagachandran K. , Anderson Alistair J. , Grantham David J. , Stephenson Janet C. 
Published: November 2006

AbstractCrypthecodinium cohnii, a marine alga used for the commercial production of docosahexaenoic acid (DHA), was cultivated in medium containing sodium acetate as principal carbon source; the pH was maintained at a constant value by addition of acetic acid, which also provided an additional carbon source in a controlled manner. The accumulation of lipid by C. cohnii in this pH‐auxostat culture was significantly greater than previously reported for batch cultures using glucose as principal carbon source. Of six strains tested in pH‐auxostat cultures, C. cohnii ATCC 30772 was the best, with the cells reaching 20 to 30 g dry weight per liter after 98 to 144 h and containing in excess of 40% (w/w) total lipid, with DHA representing approximately half of the total fatty acids in the triacylglycerol fraction. A productivity of 36 mg DHAL−1 h−1 was achieved during cultivation for 98 h using a 5% (vol/vol) inoculum, and DHA production was in excess of 3 g per liter of culture. Most of the DHA was present in neutral lipids.
Sphingophosphonolipids, phospholipids, and fatty acids from aegean jellyfish Aurelia aurita
Authors: Kariotoglou Dimitrios M. , Mastronicolis Sofia K. 
Published: November 2006

AbstractThe goal of this study is to elucidate and identify several sphingophosphonolipids from Aurelia aurita, an abundant but harmless Aegean jellyfish, in which they have not previously been described. Total lipids of A. aurita were 0.031–0.036% of fresh tissue, and the lipid phosphorus content was 1.3–1.7% of total lipids. Phosphonolipids were 21.7% of phospholipids and consisted of a major ceramide aminoethyl‐phosphonate (CAEP‐1; 18.3%), as well as three minor CAEP (II, III, IV) methyl analogs at 1.3, 1.1, and 1.0%, respectively. The remaining phospholipid composition was: phosphatidylcholine, 44.5%, including 36.2% glycerylethers; phosphatidylethanolamine, 18.6%, including 4.5% glycerylethers; cardiolipin, 5.6%; phosphatidylinositol, 2.6%; and lysophosphatidylcholine, 5.0%. In CAEP‐1; saturated fatty acids of 14–18 carbon chain length were 70.8% and were combined with 57.3% dihydroxy bases and 23.4% trihydroxy bases. The suite of the three minor CAFP methyl analogs were of the same lipid class based on the head group, but they separated into three different components because of their polarity as follows: CAEP‐II and CAEP‐III differentiation from the major CAEP‐I was mainly due to the increased fatty acid unsaturation and not to a different long‐chain base, but the CAEP‐IV differentiation from CAEP‐I, apart from fatty acid unsaturation, was due to the increased content of hydroxyl groups originated from both hydroxy fatty acids and trihydroxy long‐chain bases. Saturated fatty acids were predominant in total (76.7%), polar (83.0%), and neutral lipids (67.6%) of A. aurita. The major phospholipid components of A. aurita were comparable to those previously found in a related organism (Pelagia noctiluca), which can injure humans.
Separation and identification of phospholipid peroxidation products
Authors: Milne Ginger L. , Porter Ned A. 
Published: November 2006

AbstractThe molecular species in mixtures of phospholipid hydroperoxides are difficult to separate and identify by typical chromatographic and mass spectrometric techniques. As reported by Havrilla and coworkers, silver ion coordination ionspray mass spectrometry (CIS‐MS) has proven to be a powerful technique for the identification of mixtures of hydroperoxides. This ionization technique, which involves the formation of Ag+ adducts of the hydroperoxides, provides valuable, unambiguous structural information about the hydroperoxides. Herein, we report a method for the analysis and identification of phospholipid hydroperoxides using CIS‐MS. We also report an improved method for the separation of phospholipid hydroperoxides by reversed‐phase high‐performance liquid chromatography (RP‐HPLC), which, for the first time, separates some of the hydroperoxide isomers. CIS‐MS can be coupled with this RP‐HPLC method by the addition of AgBF4 to the mobile phase or to the HPLC effluent postcolumn, thus allowing powerful HPLC‐MS techniques to be used to identify complex mixtures of phospholipid hydroperoxides.
Plasma kinetics of a cholesterol‐rich emulsion in young, middle‐aged, and elderly subjects
Authors: Pinto Lígia B. , Wajngarten Mauricio , Silva Edson L. , Vinagre Carmen C. , Maranhão Raul C. 
Published: November 2006

AbstractLow density lipoprotein (LDL) plasma concentration is increased in the elderly. In this group, the incidence of coronary artery disease (CAD) is greater and LDL remains an important risk factor for CAD development. In this study, the plasma kinetics of a cholesterol‐rich emulsion that binds to LDL receptors was studied in 10‐subject groups of the elderly (70±4 yr), middle‐aged (42±5 yr) and young (23±2 yr). All were normolipidemic, nonobese, nondiabetic subjects who did not have CAD. The emulsion was labeled with 14C‐cholesteryl oleate and injected intravenously into the subjects. Blood samples were drawn at regular intervals over 24 h to determine the plasma decay curve of the emulsion radioactive label and to estimate its plasma fractional clearance rate (FCR, in h−1). FCR of the emulsion label was smaller in elderly compared to young subjects (0.032±0.035 and 0.071±0.049 h−1, respectively; mean±SD, P<0.05). FCR of the middle‐aged subjects (0.050±0.071 h−1) was intermediate between the values of the elderly and young subjects, although not statistically different from them. A negative correlation was found between the emulsion FCR and subjects’ age (r=−0.47, P=0.008). We conclude that aging is accompanied by progressively diminished clearance of the emulsion cholesterol esters and, by analogy, of the native LDL.
Incorporation of α‐tocopherol in marine lipid‐based liposomes: in vitro and in vivo studies
Authors: Nacka Fabienne , Cansell Maud , Méléard Philippe , Combe Nicole 
Published: November 2006

AbstractLiposomes made from a natural marine lipid extract and containing a high polyunsaturated n−3 fatty lipid ratio were envisaged as oral route vectors and a potential α‐tocopherol supplement. The behavior of vesicles obtained by simple filtration and of giant vesicles prepared by electroformation was investigated in gastrointestinal‐like conditions. The influence of α‐tocopherol incorporation into liposomes was studied on both physical and chemical membrane stability. Propanal, as an oxidation product of n−3 polyunsaturated fatty acids, was quantified by static headspace gas chromatography when α‐tocopherol incorporation into liposome ratios ranged from 0.01 to 12 mol%. Best oxidative stability was obtained for liposomes that contained 5 mol% α‐tocopherol. Compared to the other formulas, propanal formation was reduced, and time of the oxidation induction phase was longer. Moreover, α‐tocopherol induced both liposome structural modifications, evidenced by turbidity, and phospholipid chemical hydrolysis, quantified as the amount of lysophospholipids. This physicochemical liposome instability was even more pronounced in acid storage conditions, i.e., α‐tocopherol incorporation into liposome membranes accelerated the structural rearrangements and increased the rate of phospholipid hydrolysis. In particular, giant vesicles incubated at pH 1.5 underwent complex irreversible shape transformations including invaginations. In parallel, the absorption rate of α‐tocopherol was measured in lymph‐cannulated rats when α‐tocopherol was administrated, as liposome suspension or added to sardine oil, through a gastrostomy tube. α‐Tocopherol recovery in lymph was increased by almost threefold, following liposome administration. This may be related to phospholipids that should favor α‐tocopherol solubilization and to liposome instability in the case of a high amount of α‐tocopherol in the membranes. A need to correlate results obtained from in vitro liposome behavior with in vivo lipid absorption was demonstrated by this study.