Abstract:
:Supersaturation and rapid nucleation of cholesterol in bile are of key importance in the pathogenesis of cholesterol gallstones. While the effects of bile acids and phospholipids on cholesterol saturation of bile have been extensively studied, their influence on the cholesterol nucleation time has not been compared. We, therefore, investigated whether increases of bile acid or phospholipid concentrations in bile by in vitro supplementation affect the cholesterol nucleation time. Bile samples were obtained at surgery from patients with cholesterol gallstones. Prior to the nucleation assay the bile samples were divided into 0.5-ml aliquots and supplemented with 1.25, 2.5, 5.0, and 10.0 mumol/ml of different phosphatidylcholines (PC-dimyristoyl, PC-dipalmitoyl, PC-distearoyl, and extracted biliary PCs) or with 5.0, 10.0, and 20.0 mumol/ml of bile acids (glycine or taurine conjugates of cholic acid, deoxycholic acid, or chenodeoxycholic acid). The increase of phosphatidylcholine or bile acid concentration decreased the mean cholesterol saturation index to a similar extent (PC: 0.1-0.3; BA: 0.1-0.2). Supplementations of bile with increasing amounts of synthetic or biliary PCs caused a marked prolongation of the nucleation time in bile from 1.5 +/- 0.2 up to > or = 21 days or 2.5 +/- 0.7 up to > or = 21 days. Concurrently, biliary cholesterol was shifted from vesicles to mixed micelles and the cholesterol/phospholipid ratio of the remaining vesicles was progressively lowered. In contrast, the addition of bile acids to gallbladder bile did not affect the cholesterol nucleation time (2.2 +/- 0.3 days), the percentage of vesicular cholesterol, or the cholesterol/phospholipid ratio of vesicles and micelles.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Jüngst D,Lang T,Huber P,Lange V,Paumgartner Gsubject
Has Abstractpub_date
1993-09-01 00:00:00pages
1457-64issue
9eissn
0022-2275issn
1539-7262journal_volume
34pub_type
杂志文章abstract::In an effort tao simulate the effects of insulin on fat cells prepared from fresh adipose tissue, pieces of epididymal adipose tissue were cultured in a medium containing charcoal-treated bovine serum albumin (BSA) with a gas phase of 100% O2. Using this system, the insulin effect on [1-14C]glucose oxidation was retai...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1982-02-01 00:00:00
abstract::In addition to its role in the uptake of apolipoprotein B (apoB)-containing lipoproteins, apoE promotes hepatic very low density lipoprotein-triglyceride (VLDL-TG) production in animal models. However, it is not known if apoE increases the amount of TG per VLDL particle or the number of VLDL particles secreted. VLDL-a...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2000-10-01 00:00:00
abstract::We evaluated the role of sterol-regulatory element binding protein (SREBP)-1c/peroxisome proliferator activated receptor-gamma (PPARgamma) pathway on heart lipotoxicity in patients with metabolic syndrome (MS) and aortic stenosis (AS). Echocardiographic parameters of heart function and structural alterations of LV spe...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.P900032-JLR200
更新日期:2009-11-01 00:00:00
abstract::Cigarette smokers have reduced levels of plasma high density lipoprotein (HDL) compared to nonsmokers and are at risk of premature cardiovascular disease. Previous work from this laboratory has shown that exposure of human plasma to gas-phase cigarette smoke (CS) inhibited the activity of lecithin:cholesterol acyltran...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1995-02-01 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::SREBP cleavage-activating protein (Scap) is an endoplasmic reticulum membrane protein required for cleavage and activation of sterol regulatory element-binding proteins (SREBPs), which activate the transcription of genes in sterol and fatty acid biosynthesis. Liver-specific loss of Scap is well tolerated; hepatic synt...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M059709
更新日期:2015-08-01 00:00:00
abstract::The metabolism of chenodeoxycholic acid by Pseudomonas sp. NCIB 10590 under strict anaerobic conditions was studied. A range of unsaturated acidic and neutral metabolites were isolated and identified. The major acidic product was chola-4,6-dien-3-one-24-oic acid whilst the major neutral product was androsta-4,6-dien-3...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1983-09-01 00:00:00
abstract::We have recently reported that the human apolipoprotein A-I (apoA-I) and apolipoprotein C-III (apoC-III) genes are physically linked and that the presence of a DNA insertion in the apoA-I gene is correlated with apoA-I-apoC-III deficiency in patients with premature atherosclerosis. In addition, the presence of a polym...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1985-04-01 00:00:00
abstract::Membranes of mammalian cells contain lysophosphatidic acid acyltransferase (LPAAT) activities that catalyze the acylation of sn-1-acyl lysophosphatidic acid (lysoPA) to form phosphatidic acid. As the biological roles and biochemical properties of the six known LPAAT isoforms have yet to be fully elucidated, we have ch...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M500435-JLR200
更新日期:2006-03-01 00:00:00
abstract::Sphingolipids are ubiquitous components of eukaryotic cells that regulate various cellular functions. In many cell types, a fraction of sphingolipids contain 2-hydroxy fatty acids, produced by fatty acid 2-hydroxylase (FA2H), as the N-acyl chain of ceramide [hydroxyl fatty acid (hFA)-sphingolipids]. FA2H is highly exp...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M800666-JLR200
更新日期:2009-06-01 00:00:00
abstract::In the present study, the effects of taxifolin, a plant flavonoid, on lipid, apolipoprotein B (apoB), and apolipoprotein A-I (apoA-I) synthesis and secretion were determined in HepG2 cells. Pretreatment of cells with (+/-)-taxifolin led to an inhibition of cholesterol synthesis in a dose- and time-dependent manner, wi...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2000-12-01 00:00:00
abstract::Gel-permeation chromatography on Sephadex LH-20, using ethanol as eluent, permits the resolution of neutral hydroxy lipids according to molecular size. The influence of molecular shape, functional groups, chain lengths, and degree of unsaturation, as well as the effect of the eluent on the elution pattern are discusse...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1970-03-01 00:00:00
abstract::Atherosclerosis is a chronic inflammatory response characterized by the accumulation of cells of innate and acquired immune systems within the intima of the arterial wall. Macrophages are the predominant participant in innate immune responses in atherosclerosis. Protein receptors expressed by macrophages and endotheli...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:10.1194/jlr.R400015-JLR200
更新日期:2005-03-01 00:00:00
abstract::To study the mechanisms of hepatic HDL formation, we investigated the roles of ABCA1, ABCG1, and SR-BI in nascent HDL formation in primary hepatocytes isolated from mice deficient in ABCA1, ABCG1, or SR-BI and from wild-type (WT) mice. Under basal conditions, in WT hepatocytes, cholesterol efflux to exogenous apoA-I w...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M017079
更新日期:2012-03-01 00:00:00
abstract::A simple, rapid, inexpensive method for isolating disaturated phosphatidylcholine from adult rat lung has been devised. Total lipids are reacted with osmium tetroxide dissolved in carbon tetrachloride, and the disaturated phosphatidylcholine is isolated on a column of neutral alumina. More than 99% of the fatty acids ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1976-05-01 00:00:00
abstract::Autotaxin (ATX), which is highly expressed and secreted by adipocytes, functions as the key enzyme to generate lysophosphatidic acid (LPA) from lysophosphatidylcholine. Adipose tissue is the main source of circulating ATX that modulates plasma LPA levels. Upregulation of ATX expression in obese patients and mice is cl...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M075655
更新日期:2017-11-01 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::Ac-hE18A-NH2 is a dual-domain apoE mimetic peptide that possesses the putative receptor binding domain from apoE (LRKLRKRLLR, denoted hE; residues 141-150) covalently attached to lipid-associating peptide 18A. Like apoE, Ac-hE18A-NH2 reduces plasma cholesterol in animal models and exhibits anti-inflammatory properties...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M085985
更新日期:2018-11-01 00:00:00
abstract::Fatty acid binding protein 4 (FABP4), also known as adipocyte FABP or aP2, is secreted from adipocytes in association with lipolysis as a novel adipokine, and elevated serum FABP4 level is associated with obesity, insulin resistance, and atherosclerosis. However, little is known about the modulation of serum FABP4 lev...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M059469
更新日期:2015-12-01 00:00:00
abstract::Total serum free fatty acids (FFAt) levels provide an important measure of the physiologic state. Most of the FFA in serum is bound to albumin; a small portion, however, is unbound. This study presents the first measurements of serum unbound free fatty acid (FFAu) concentrations. These measurements were made possible ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1995-02-01 00:00:00
abstract::The objectives of this study were to characterize the effects of plasma lipoproteins on prostacyclin (PGI2) production by the Langendorff-perfused rabbit heart, and to determine the mechanism of lipoprotein-induced cardiac PGI2 production. PGI2 production by perfused rabbit hearts was stimulated by injections of rabbi...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1986-05-01 00:00:00
abstract::The proton NMR spectra of the N-methyl choline region of normal and lecithin:cholesterol acyltransferase (LCAT)-deficient lipoproteins and of egg yolk phosphatidylcholine-cholesterol 55:45 (mol %) vesicle mixtures have been examined in the presence and absence of manganous sulfate as a line-broadening reagent. Mangano...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1989-05-01 00:00:00
abstract::In vitro studies show that docosahexaenoic acid (DHA) can be released from membrane phospholipid by Ca(2+)-independent phospholipase A(2) (iPLA(2)), Ca(2+)-independent plasmalogen PLA(2) or secretory PLA(2 (sPLA2)), but not by Ca(2+)-dependent cytosolic PLA(2) (cPLA2), which selectively releases arachidonic acid (AA)....
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M006262
更新日期:2010-08-01 00:00:00
abstract::Rats were fed either rat chow (control), chow + 20% olive oil (olive oil), or chow + 20% olive oil + 2% cholesterol (olive oil/cholesterol) as a single meal to study the short-term effects of fat and the above combination of fat/cholesterol-containing diets on plasma apoB concentration and its influence on the distrib...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1985-08-01 00:00:00
abstract::Rat brain increases in weight after birth in three stages: (I) rapidly for the first 2 weeks, (II) at a lower rate from 2 to 5 weeks, and (III) at a still lower rate from 5 weeks to 5 months. During the succeeding period, designated IV, it maintains constant weight up to 1 year of age. Brain ganglioside content increa...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1966-01-01 00:00:00
abstract::In mice, the yolk sac appears to play a crucial role in nourishing the developing embryo, especially during embryonic days (E) 7;-10. Lipoprotein synthesis and secretion may be essential for this function: embryos lacking apolipoprotein (apo) B or microsomal triglyceride transfer protein (MTP), both of which participa...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-11-01 00:00:00
abstract::Bile acids labeled with 3H on the sterol nucleus lose a substantial fraction of label during enterohepatic cycling and conversion to secondary bile acids. We tested the isotopic stability of a side-chain 3H label, [22,23-3H]cholic acid in humans. The 3H-labeled compound was administered simultaneously with [24-14C]cho...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1996-02-01 00:00:00
abstract::As 5-lipoxygenase (5-LO) is an emerging target in obesity and insulin resistance, we have investigated whether this arachidonate pathway is also implicated in the progression of obesity-related fatty liver disease. Our results show that 5-LO activity and 5-LO-derived product levels are significantly elevated in the li...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M800101-JLR200
更新日期:2008-12-01 00:00:00
abstract::Spontaneously transformed mouse fibroblasts (Balb/c 3T12-3 cells) displayed an increased adhesion when cultured in the presence of 10(-6) M all-trans retinol and acquired morphological characteristics of the normal phenotype. Thus it was of interest to investigate the metabolism of [15-(14)C]retinol in this system. Wi...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1979-03-01 00:00:00
abstract::Cholesterol exists within the hepatocyte as free cholesterol and cholesteryl ester. The proportion of intrahepatic cholesterol in the free or ester forms is governed in part by the rate of cholesteryl ester formation by acyl-coenzyme A:cholesterol acyltransferase (ACAT) and cholesteryl ester hydrolysis by neutral chol...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1989-11-01 00:00:00