Abstract:
:Essential fatty acids (EFA) are important structural and functional components of cell membranes. Their deficiency has been associated with several clinical and biochemical abnormalities. In the present study, the lipid profile as well as the concentration, composition, and metabolism of lipoproteins were examined in rats rendered EFA-deficient over a period of 12 weeks. Changes in plasma fatty acids mainly induced an increase of palmitoleic (16:1 n-7) and eicosatrienoic (20:3 n-9) acids, while linoleic (18:2 n-6), arachidonic (20:4 n-6), linolenic (18:3 n-3), and docosahexaenoic (22:6 n-3) acids were decreased. The results show increased concentrations of free fatty acids (FFA) (P less than 0.001), triglycerides (P less than 0.001), total cholesterol (P less than 0.02), free cholesterol (P less than 0.005), and phospholipids (P less than 0.05) when compared to pair-fed controls. Similar levels of cholesteryl esters were found in the two groups, and lecithin: cholesterol acyltransferase activity (nmol/100 microliters plasma per h) (8.98 +/- 1.44 vs 8.72 +/- 0.50) did not differ. On the other hand, postheparin extrahepatic lipoprotein lipase (LPL) activity was significantly (P less than 0.002) decreased (5.96 +/- 0.29 vs 7.29 +/- 0.68 mumol FFA/ml per h) and could account for the hypertriglyceridemia as well for the relative triglyceride enrichment of very low density lipoprotein, intermediate density lipoprotein, and low density lipoprotein particles. This enzymatic depletion of LPL was mainly due to the adipose tissue, since a higher level (P less than 0.001) of hepatic lipase (325.8 +/- 16.0 vs 130.8 +/- 9.5 nmol FFA/mg protein per h) was found in liver acetone powder extracts.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Levy E,Thibault L,Garofalo C,Messier M,Lepage G,Ronco N,Roy CCsubject
Has Abstractpub_date
1990-11-01 00:00:00pages
2009-17issue
11eissn
0022-2275issn
1539-7262journal_volume
31pub_type
杂志文章abstract::This study was undertaken to determine the mechanisms that regulate cholesterol synthesis in vivo and to quantitate the relative importance of the liver and extrahepatic tissues as sites for sterol synthesis. Rats were administered [3H]water intravenously and killed 1 hour later. The amount of [3H]water incorporated i...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1980-03-01 00:00:00
abstract::The early premalignant liver provides a model in which to study metabolic alterations that may be permissive for the development of full malignancy. Although there are biochemical changes in this model, there are no detectable morphological ones when compared with a normal, fully differentiated liver. The maintenance ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1990-05-01 00:00:00
abstract::This report describes the isolation of sarcosylsarcosine conjugate of ursodeoxycholic acid (UDCA) formed during the synthesis of sarcoUDCA by the mixed anhydride method. The compound was characterized by its chemical ionization mass spectrum. The diamino acid conjugate was formed only when the free amino acid was used...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1989-05-01 00:00:00
abstract::Cholesterol 7alpha-hydroxylase (CYP7A1) plays a crucial role in cholesterol metabolism and has been implicated in genetic susceptibility to atherosclerosis. Thus, an understanding of its transcriptional regulation is of considerable importance. We evaluated the effect of a common -203A>C polymorphism in the CYP7A1 pro...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M800364-JLR200
更新日期:2008-12-01 00:00:00
abstract::The initial studies of the metabolism of arachidonic acid (AA) by the cytochrome P450 (P450) hemeproteins sought to: a) elucidate the roles for these enzymes in the metabolism of endogenous pools of the FA, b) identify the P450 isoforms involved in AA epoxidation and ω/ω-1 hydroxylation, and c) explore the biological ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.R087882
更新日期:2018-11-01 00:00:00
abstract::Thioesterase superfamily member 1 (Them1; synonyms acyl-CoA thioesterase 11 and StarD14) is highly expressed in brown adipose tissue and limits energy expenditure in mice. Them1 is a putative fatty acyl-CoA thioesterase that comprises tandem hot dog-fold thioesterase domains and a lipid-binding C-terminal steroidogeni...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M029538
更新日期:2012-12-01 00:00:00
abstract::A facile procedure is described for the preparation of [14C]epicholesterol from [14C]cholesterol. Cholesterol is first converted to cholesteryl mesylate, which is treated with cesium acetate and 18-crown-6 in refluxing toluene to give epicholesteryl acetate. The latter is hydrolyzed, without isolation, with potassium ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1990-01-01 00:00:00
abstract::Endothelial dysfunction is a key step in atherosclerosis development. Our recent studies suggested that oxLDL-induced increase in endothelial stiffness plays a major role in dyslipidemia-induced endothelial dysfunction. In this study, we identify oxysterols, as the major component of oxLDL, responsible for the increas...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M027102
更新日期:2012-07-01 00:00:00
abstract::The purpose of the present study was to examine the regulation of levels of apolipoprotein B (apoB) mRNA and its protein by cytokines in HepG2 cells. A dose-dependent increase in apoB mRNA levels was observed in the presence of either interleukin-1beta (IL-1beta) or IL-6 alone. This increase occurred as early as 1 h a...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1998-01-01 00:00:00
abstract::The novel acyl-CoA:cholesterol acyltransferase (ACAT) inhibitor CP-113,818 has been characterized in vitro against ACAT isolated from liver and intestine from a variety of species including human subjects, and in vivo in cholesterol-fed rats, hamsters, rabbits, and two species of nonhuman primates. CP-113,818 is a pot...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1994-10-01 00:00:00
abstract::The biosynthesis of prostaglandins by isolated rat adrenocortical cells has been studied by determinations of products formed during incubations with labeled arachidonic acid and by radioimmunoassays. Analysis by thin-layer chromatographic separation of silicic acid column fractions indicated that PGE2, PGA2, (B2) and...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1979-01-01 00:00:00
abstract::Alcoholic liver disease (ALD) is the most prevalent type of chronic liver disease with significant morbidity and mortality worldwide. ALD begins with simple hepatic steatosis and progresses to alcoholic steatohepatitis, fibrosis, and cirrhosis. The severity of hepatic steatosis is highly associated with the developmen...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:10.1194/jlr.R119000547
更新日期:2020-04-01 00:00:00
abstract::Three 14C-labeled 22-carbon polyunsaturated fatty acids, 7,10,13,16-[14C]docosatetraenoic acid (22:4(n-6)), 7,10,13,16,19-[14C]docosapentaenoic acid (22:5(n-3)), and 4,7,10,13,16,19-[14C]docosahexaenoic acid (22:6(n-3)), were compared with [3H]arachidonic acid (20:4(n-6] and [14C]linoleic acid (18:2(n-6)) to character...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1986-11-01 00:00:00
abstract::A device for the simultaneous evaporation of six samples under separately controlled streams of nitrogen is described. ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1967-05-01 00:00:00
abstract::The two oxysterols, 27-hydroxycholesterol (27OH) and 24S-hydroxycholesterol (24OH), are both inhibitors of cholesterol synthesis and activators of the liver X receptor (LXR) in vitro. Their role as physiological regulators under in vivo conditions is controversial, however. In the present work, we utilized a previousl...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M034124
更新日期:2013-04-01 00:00:00
abstract::Cyclophosphamide injection into the fasted rabbit induces a hypertriglyceridemia (4.6 mM vs. 0.8 mM in controls) and a defect of lipoprotein lipase (LPL), as measured in post-heparin plasma (PHP). In contrast, administration of the drug into fed animals tends to increase PHP-LPL. The effects of cyclophosphamide on LPL...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1993-01-01 00:00:00
abstract::Sequence homology indicates the existence of three human cytosolic acyl protein thioesterases, including APT1 that is known to depalmitoylate H- and N-Ras. One of them is the lysophospholipase-like 1 (LYPLAL1) protein that on the one hand is predicted to be closely related to APT1 but on the other hand might also func...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M019851
更新日期:2012-01-01 00:00:00
abstract::A gas-liquid chromatographic-mass spectrometric method of determining the position of oxygen atoms on polyfunctional fatty acids has been explored. The method consists of reduction of keto, hydroperoxy, epoxy, and carboxylic acid groups with LiAlH(4) to the corresponding alcohols; trimethylsilylation with bis(trimethy...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1969-03-01 00:00:00
abstract::In addition to functioning as detergents that aid digestion of dietary lipids in the intestine, some bile acids have been shown to exhibit antimicrobial activity. However, detailed information on the bactericidal activities of the diverse molecular species of bile acid in humans and rodents is largely unknown. Here, w...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M075143
更新日期:2017-06-01 00:00:00
abstract::Isotopic measurement of biosynthetic rates of lipids in VLDL particles has long posed difficult technical problems. In this review, key methodologic issues and recent technical advances are discussed. A common problem for all biosynthetic measurements is the requirement to measure isotopic labeling of the true intrace...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:10.1194/jlr.R600018-JLR200
更新日期:2006-08-01 00:00:00
abstract::When grown in the presence of bile acids, two strains of Clostridium limosum were found to contain significant amounts of NADP-dependent 7 alpha/7 beta-hydroxysteroid dehydrogenase and NAD-dependent 7 alpha-hydroxysteroid dehydrogenase which were active against conjugated and unconjugated bile acids. No measurable act...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1985-03-01 00:00:00
abstract::In an attempt to understand the applicability of various animal models to dyslipidemia in humans and to identify improved preclinical models for target discovery and validation for dyslipidemia, we measured comprehensive plasma lipid profiles in 24 models. These included five mouse strains, six other nonprimate specie...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M019927
更新日期:2012-01-01 00:00:00
abstract::We used a mouse C57BL/6J×CASA/Rk intercross to map a locus on chromosome 14 that displayed a gender-dependent effect on cholesterol absorption from the intestine. Studies in congenic animals revealed a complex locus with multiple operating genetic determinants resulting in alternating gender-dependent phenotypic effec...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M034579
更新日期:2013-03-01 00:00:00
abstract::The apoE gene exhibits two common polymorphisms that have been associated with both coronary artery disease and Alzheimer's disease. The polymorphisms create the three allelic isoforms E2, E3, and E4 which are encoded by Cys;-Cys, Cys;-Arg, and Arg;-Arg at amino acid positions 112 and 158, respectively. Numerous metho...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract::An online, two-dimensional (2D) liquid chromatography (LC) quadrupole time-of-flight mass spectrometry (QToF-MS) method was developed for lipid profiling of rat peritoneal surface layers, in which the lipid classes and species could be simultaneously separated in one injection with a significantly increased sensitivit...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D007567
更新日期:2010-09-01 00:00:00
abstract::Synthesis of apolipoprotein (apo)E in hepatocytes leads to both secretion and retention in cell surface pools. Inclusion of Brefeldin A to HepG2 cells prompted a rapid decrease of cell surface apoE to about 37% of control values after a 3-h incubation. The t(1/2) for this dynamic pool was estimated to be 15 min. In co...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2001-09-01 00:00:00
abstract::The sequences necessary for liver-specific expression of the apolipoprotein (apo) E gene have been shown to reside 3' to the gene, within the apoE/C-I/C-II gene cluster, but have not been precisely characterized. Utilizing a transient transfection reporter gene assay based on the apoC-II promoter, we have localized a ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1993-10-01 00:00:00
abstract::C26 Bile of the 24-nor-5beta-cholestane series were prepared starting from methyl cholate. A Grignard reaction of methyl magnesium iodide with methyl cholate yielded 24-nor-5beta-cholestane-3alpha, 7alpha, 12alpha, 25-tetrol which was dehydrated TO FORM a mixture of 24-nor-5beta-cholest-23-ene-3alpha, 7alpha, 12 alpha...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1976-09-01 00:00:00
abstract::Lysophospholipid (LP) research has experienced a period of renaissance with the discovery of the lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P) receptors in the late 1990s. Vertebrate LP receptors regulate embryogenesis, vascular development, neurogenesis, uterine development, oocyte survival, immune ce...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:10.1194/jlr.R800047-JLR200
更新日期:2009-04-01 00:00:00
abstract::A new method for the purification of apolipoprotein H by affinity chromatography followed by continuous-elution electrophoresis is described. It is both simpler and less complicated than the chromatographic and electrophoretic methods usually used. In addition, apolipoprotein H is isolated in a pure, structurally uncl...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1996-04-01 00:00:00