Abstract:
:The recognition that the 7 alpha-hydroxylation of 27-hydroxycholesterol is catalyzed by an enzyme that is different from cholesterol 7 alpha-hydroxylase raises the question as to the number of similar enzymes that may be present in liver and subserve bile acid synthesis. Thus, both 3 beta-hydroxy-5-cholestenoic acid and 3 beta-hydroxy-5-cholenoic acid, further oxidation products derived from 27-hydroxycholesterol, are also 7 alpha-hydroxylated during their metabolism to chenodeoxycholic acid. Using a microsomal fraction of hamster liver and competition plot analysis, we found that the 7 alpha-hydroxylase activity for the acid substrates was approximately one-tenth that found for 27-hydroxycholesterol. Mixtures of the different substrates did not depress the total rate of 7 alpha-hydroxylation. The evidence supports the view that these substrates share the same catalytic site on a single enzyme.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Lee C,Martin KO,Javitt NBsubject
Has Abstractpub_date
1996-06-01 00:00:00pages
1356-62issue
6eissn
0022-2275issn
1539-7262journal_volume
37pub_type
杂志文章abstract::Major neutral glycosphingolipid components were extracted from Sporothrix schenckii, a dimorphic fungus exhibiting a hyphal saprophytic phase and a yeast parasitic phase responsible for chronic mycotic infections in mammalian hosts. These components, one from the mycelial form and two from the yeast form, were purifie...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2000-05-01 00:00:00
abstract::Binding of the medium-chain fatty acids (MCFA), octanoic (OCT) and decanoic (DEC) acid, to human serum albumin (HSA) has been studied by 13C NMR spectroscopy. NMR spectra at 35 degrees C showed an apparently homogeneous binding environment (a single, narrow resonance for the 13C-enriched carboxyl carbon) at different ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1994-03-01 00:00:00
abstract::In vitro experiments have demonstrated that exogenous phospholipid transfer protein (PLTP), i.e. purified PLTP added to macrophage cultures, influences ABCA1-mediated cholesterol efflux from macrophages to HDL. To investigate whether PLTP produced by the macrophages (i.e., endogenous PLTP) is also part of this process...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M600051-JLR200
更新日期:2006-08-01 00:00:00
abstract::HDL plays crucial roles at multiple stages of the pathogenesis of atherosclerosis. AMP-activated protein kinase (AMPK) is a therapeutic candidate for the treatment of cardiovascular disease. However, the effect of AMPK activation on HDL functionality has not been established in vivo. We assessed the effects of pharmac...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M073270
更新日期:2017-08-01 00:00:00
abstract::To assess the relationship between cholesterol synthesis and feedback inhibition of bile acid synthesis, we studied seven normal human subjects taking three different doses of chenodiol, 0, 5, and 15 mg/kg per day: once while taking no lovastatin and again while taking lovastatin 80 mg/day. Lovastatin and both doses o...
journal_title:Journal of lipid research
pub_type: 临床试验,杂志文章,随机对照试验
doi:
更新日期:1994-08-01 00:00:00
abstract::We previously have shown that LDL-R354, a truncated low density lipoprotein (LDL) receptor, is a calcium binding protein. LDL-R354 is composed of the ligand binding domain and repeat A of the EGF precursor homology domain of the full-length human LDL receptor. We also found that Ca2+ was required for the interaction b...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract::Using the "ghost method" previously applied to study the binding of palmitate to bovine serum albumin (BSA) (Bojesen, I. N., and E. Bojesen. 1992. J. Lipid Res. 33: 1327-1334) we have measured the water-phase concentrations of arachidonate (AR) and oleate (OL) in 165 mM KCl and in 165 mM NaCl, 2 mM phosphate buffer at...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1994-05-01 00:00:00
abstract::Methods were developed for the determination of HMG CoA (3-hydroxy-3-methylglutaryl CoA) reductase activity in subcellular fractions of intestinal mucosa and liver of Wistar strain rats. In the liver, reductase activity was located exclusively in the microsomal fraction. In the intestinal mucosa, activity was found in...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1972-05-01 00:00:00
abstract::Maintaining cellular lipid homeostasis is crucial to oxidative tissues, and it becomes compromised in obesity. Lipid droplets (LD) play a central role in lipid homeostasis by mediating fatty acid (FA) storage in the form of triglyceride, thereby lowering intracellular levels of lipids that mediate cellular lipotoxicit...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M017939
更新日期:2011-12-01 00:00:00
abstract::Lipoprotein metabolism can be studied by the analysis of lipoprotein production in cell culture. An inherent problem in such an analysis is the low concentration of lipoproteins in culture supernatants. The difficulty comes from the fact that the samples must be concentrated prior to any analysis. The concentrating me...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1995-10-01 00:00:00
abstract::Triglyceride-rich lipoproteins derived from ten normo- and hyperlipidemic apoE-2 homozygotes were analyzed for their composition, beta-VLDL content, and their ability to induce cholesteryl ester storage in macrophages. In six of these probands apoE sequence analysis revealed that the cysteine residues were at position...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1985-03-01 00:00:00
abstract::The accumulation of phosphatidylcholine hydroperoxide (PCOOH), a primary oxidation product of phosphatidylcholine (PC), in blood plasma and tissues has been observed in various pathological conditions, including atherosclerosis. However, the biological roles of PCOOH in these conditions remain unknown. To estimate the...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M800582-JLR200
更新日期:2009-05-01 00:00:00
abstract::ABCA1 exports cholesterol and phospholipids from cells by a multistep pathway that involves forming cell surface lipid domains, solubilizing these lipids by apolipoproteins, binding of apolipoproteins to ABCA1, and activating signaling processes. Here we used a mutational analysis approach to evaluate the relationship...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M800366-JLR200
更新日期:2009-02-01 00:00:00
abstract::We analysed the sensitivity to beta-adrenoceptor agonists in epididymal adipose cells from rats submitted to a stress protocol previously reported to induce alterations in sensitivity to catecholamines in cardiac tissue from rats. Food intake and body weight were lower, whereas adipocytes basal lipolysis was higher (c...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-09-01 00:00:00
abstract::Ceramidases catalyze the cleavage of ceramides into sphingosine and fatty acids. Previously, we reported on the use of the RBM14 fluorogenic ceramide analogs to determine acidic ceramidase activity. In this work, we investigated the activity of other amidohydrolases on RBM14 compounds. Both bacterial and human purifie...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D061564
更新日期:2015-10-01 00:00:00
abstract::Lysophosphatidylcholine (lysoPC) is a bioactive phospholipid that is involved in atherogenesis and inflammatory processes. However, the present understanding of mechanisms whereby lysophosphatidylcholine exerts its pathophysiological actions is incomplete. In the present work, we show that lysoPC stimulates phospholip...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-06-01 00:00:00
abstract::Endothelial lipase (EL) is a triglyceride lipase gene family member that has high phospholipase and low triglyceride lipase activity. The aim of this study was to determine whether the phospholipase activity of EL is sufficient to remodel HDLs into small particles and mediate the dissociation of apolipoprotein A-I (ap...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M400212-JLR200
更新日期:2005-05-01 00:00:00
abstract::Previous studies have shown that antibodies to cubulin, a receptor on the yolk sac that binds high density lipoproteins (HDL) and cobalamin, induce fetal abnormalities. Mice with markedly low concentrations of plasma HDL-cholesterol (HDL-C) give birth to healthy pups, however. To establish whether maternal HDL-C has a...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2000-03-01 00:00:00
abstract::Previous in vitro studies have revealed that oxidized low density lipoprotein (OxLDL) has negative effects on the proliferation and activity of endothelial progenitor cells (EPCs). Here, we evaluated the effect of OxLDL on the therapeutic potential of EPCs in ischemia-induced neovascularization. EPCs derived from mobi...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M600251-JLR200
更新日期:2007-03-01 00:00:00
abstract::Very few studies have investigated the interrelations between proprotein convertase subtilisin/kexin type 9 (PCSK9) metabolism, cholesterol synthesis, and cholesterol absorption. We aimed to address this issue in a large clinical trial of 245 patients with hypercholesterolemia. Serum lipids, PCSK9, lathosterol (choles...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.P088583
更新日期:2019-01-01 00:00:00
abstract::SW-13 adrenal tumor cells that lack detectable intermediate filaments (IF-free) exhibit an impaired capacity to esterify lipoprotein-derived cholesterol compared with cells that contain vimentin filaments. IF-free cells were found to synthesize and secrete significant amounts of apoE, while apoE secretion was nearly u...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-08-01 00:00:00
abstract::The extent of oxidoreduction of the 3 alpha-, 7 alpha- and 12 alpha-hydroxyl groups in bile acids during the enterohepatic circulation in man was studied with the use of [3 beta-3H]-labeled deoxycholic acid and cholic acid, [7 beta-3H]-labeled cholic acid, and [12 beta-3H]-labeled deoxycholic acid and cholic acid. Eac...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1986-02-01 00:00:00
abstract::Inflammation has been proposed to impair HDL function and reverse cholesterol transport (RCT). We investigated the effects of inflammation mediated by zymosan, a yeast glucan, on multiple steps along the RCT pathway in vivo and ex vivo. Acute inflammation with 70 mg/kg zymosan impaired RCT to plasma, liver, and feces ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M011122
更新日期:2011-05-01 00:00:00
abstract::Phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) is a branched-chain fatty acid derived from dietary sources and broken down in the peroxisome to pristanic acid (2,6,10,14-tetramethylpentadecanoic acid) via alpha-oxidation. Pristanic acid then undergoes beta-oxidation in peroxisomes. Phytanic acid naturally occu...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2002-03-01 00:00:00
abstract::Hydroxy-3-methyl-glutaryl-CoA reductase (HMGR) is the rate-controlling enzyme of cholesterol synthesis, and owing to its biological and pharmacological relevance, researchers have investigated several compounds capable of modulating its activity with the hope of developing new hypocholesterolemic drugs. In particular,...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M011817
更新日期:2011-05-01 00:00:00
abstract::Extracts of urine and serum from children with cholestatic liver disease were analyzed by fast atom bombardment (FAB) mass spectrometry. About half of all spectra showed a peak at m/z 657, compatible with the presence of a glucuronidated cholestenediol sulfate. Separation by ion exchange chromatography before and afte...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1997-05-01 00:00:00
abstract::Increased plasma cholesterol is a known risk factor for cardiovascular disease. Lipoprotein particles transport both cholesterol and triglycerides through the blood. It is thought that the size distribution of these particles codetermines cardiovascular disease risk. New types of measurements can determine the concent...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M800354-JLR200
更新日期:2009-12-01 00:00:00
abstract::In this study, we have documented immunochemical properties of apolipoprotein (apo) B-containing particles (LpB) extracted from human atherosclerotic lesions obtained during vascular reconstructive surgery of patients. These properties were compared to those of particles purified from corresponding atherosclerotic pla...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1993-05-01 00:00:00
abstract::We propose a simple mathematical model to account for the coupling of secretion rates of bile salts, lecithin, and cholesterol into bile. The model assumes that: 1) molecules of "biliary" lecithin and cholesterol enter a functional compartment located in the endoplasmic reticulum of the hepatocyte from which they are ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1984-09-01 00:00:00
abstract::The quantitative isolation of total glycosphingolipids from crude lipid extracts without contamination from other lipid classes is described. The method consists of (a) acetylation of total lipids with pyridine and acetic anhydride, (b) separation of acetylated glycolipids from nonglycolipids on a magnesia-silica gel ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1971-03-01 00:00:00