Abstract：
:13C-NMR spectroscopy was used to examine the effect of side chain length on the ionization properties and transmembrane transport rate of 3 alpha,7 alpha-dihydroxy bile acids. When solubilized in taurocholate micelles, [23-13C]nor-chenodeoxycholic acid (nor-CDCA) had a pKa of 6.1, similar to that of CDCA (pKa 6.2), its C24 homologue. In unilamellar phosphatidylcholine vesicles, the pKa of nor-CDCA was 7.0, whereas that of CDCA was 6.6. Lineshape analysis indicated that the rate of ionization of nor-CDCA as a micellar solute or as a vesicle component was very slow (0.4 x 10(5) sec-1) compared to that of acetic acid in water (8.7 x 10(5) sec-1). Lineshape analysis of spectra of the protonated form of nor-CDCA at acidic bulk pH indicated that the transbilayer transport rate of nor-CDCA (580 sec-1) was six times faster than that of CDCA (100 sec-1). It is proposed that the shorter side chain of the nor-CDCA molecule causes it to reside more deeply inside the vesicle bilayer than CDCA, explaining its weaker ionization and more rapid flip-flop rate. These in vitro experiments imply that, in vivo, a given C23 nor-dihydroxy bile acid will ionize less readily when present in membranes, and it will also flip-flop faster than its C24 homologue.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Ko J,Hamilton JA,Ton-Nu HT,Schteingart CD,Hofmann AF,Small DMsubject
Has Abstractpub_date
1994-05-01 00:00:00pages
883-92issue
5eissn
0022-2275issn
1539-7262journal_volume
35pub_type
杂志文章abstract：:The hepatic synthesis of sterol was measured in the male Mongolian gerbil (Meriones unguiculatus) in vivo following the administration of [3H]water by monitoring the incorporation of radioactivity into digitonin-precipitable sterol. A diurnal rhythm in cholesterol synthesis was exhibited under conditions of ad libitum...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1981-07-01 00:00:00
abstract：:Niacin, the first antidyslipidemic drug, has been at the center stage of lipid research for many decades before the discovery of statins. However, to date, despite its remarkable effects on lipid profiles, the clinical outcomes of niacin treatment on cardiac events is still debated. In addition to its historically wel...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.S092007
更新日期：2019-04-01 00:00:00
abstract：:Niemann-Pick C1-like 1 (NPC1L1) is a recently identified protein that mediates intestinal cholesterol absorption and regulates biliary cholesterol excretion. The itineraries and kinetics of NPC1L1 trafficking remain uncertain. In this study, we have visualized movement of NPC1L1-enhanced green fluorescent protein (NPC...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M800145-JLR200
更新日期：2008-09-01 00:00:00
abstract：:The factors involved in shuttling cholesterol among cellular membranes have not been defined. Using amphotericin B selection, we previously isolated Chinese hamster ovary cell mutants expressing defects in intracellular cholesterol transport. Complementation analysis among seven mutants identified one cell line, mutan...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1997-10-01 00:00:00
abstract：:Dysbetalipoproteinemia, an uncommon but highly atherogenic mixed hyperlipidemia due to the accumulation of remnants of triglyceride-rich lipoproteins, is characterized by cholesterol-enriched VLDL that migrates in the beta-position on agarose gels. The demonstration of a broad beta-band on agarose gel electrophoresis ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.d200013-jlr200
更新日期：2003-01-01 00:00:00
abstract：:The subcellular and submitochondrial localization of CTP:phosphatidate cytidylyltransferase is altered in the Morris 7777 hepatoma. Mitochondria in this poorly differentiated tumor are the principal sites of CDP-diacylglycerol synthesis, in contrast to normal rat liver where the endoplasmic reticulum is most active. T...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1978-07-01 00:00:00
abstract：:ABCG1 and ABCG4 are highly homologous members of the ATP binding cassette (ABC) transporter family that regulate cellular cholesterol homeostasis. In adult mice, ABCG1 is known to be expressed in numerous cell types and tissues, whereas ABCG4 expression is limited to the central nervous system (CNS). Here, we show sig...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/M900250-JLR200
更新日期：2010-01-01 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：:Black tea is one of the world's most popular beverages, and its health-promoting effects have been intensively investigated. The antiobesity and hypolipidemic effects of black tea have attracted increasing interest, but the mechanisms underlying these phenomena remain unclear. In the present study, the black tea major...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M700128-JLR200
更新日期：2007-11-01 00:00:00
abstract：:It was reported previously that ceramide-1-phosphate (Cer-1-P) is mitogenic for fibroblasts (Gómez-Muñoz, A., P. A. Duffy, A. Martin, L. O'Brien, H-S. Byun, R. Bittman, and D. N. Brindley. 1995. Mol. Pharmacol. 47: 883-889; Gómez-Muñoz, A., L. M. Frago, L. Alvarez, and I. Varela-Nieto. 1997. Biochem. J. 325: 435-440)....
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M300158-JLR200
更新日期：2004-01-01 00:00:00
abstract：:Hepatic free cholesterol levels are influenced by cholesterol synthesis and ester formation, which, in turn, might regulate cholesterol secretion into bile and plasma. We manipulated the rates of hepatic cholesterol synthesis and esterification and measured biliary and very low density lipoprotein (VLDL) cholesterol s...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1992-11-01 00:00:00
abstract：:Analytical isoelectric focusing (IEF) has been applied to the study of the apolipoprotein components of rat serum high density and very low density lipoproteins. The apolipoproteins were separated on 7.5% polyacrylamide gels containing 6.8% urea, with a pH gradient of 4-6. The middle molecular weight range apolipoprot...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1977-01-01 00:00:00
abstract：:Apoliprotein (apo) B-100-containing very low density lipoprotein (VLDL) particles secreted from the liver accumulate in plasma during alimentary lipemia. To determine whether changes of VLDL composition occur in the postprandial state that may render these lipoproteins more atherogenic, apoE, C-I, C-II, and C-III, and...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1997-02-01 00:00:00
abstract：:The basic protein protamine strongly inhibited hydrolysis of triolein emulsified with soybean phosphatidylcholine (PC) by pancreatic and carboxylester lipases; 10 micrograms/ml protamine, about 1000 times lower than the concentration of bovine serum albumin for the same effect, inhibited triolein hydrolysis completely...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1996-07-01 00:00:00
abstract：:Phospholipids serve as central structural components in cellular membranes and as potent mediators in numerous signaling pathways. There are six main classes of naturally occurring phospholipids distinguished by their distinct polar head groups that contain many unique molecular species with distinct fatty acid compos...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.D051581
更新日期：2014-11-01 00:00:00
abstract：:The intestinal bacterium Eubacterium sp. strain VPI 12708 has been shown to have a bile acid 7 alpha/7 beta-dehydroxylation pathway. A large bile acid inducible (bai) operon encoding at least 9 open reading frames has been cloned and sequenced from this bacterium. The baiE gene from this operon has been subcloned and ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1996-06-01 00:00:00
abstract：:The HDL Atherosclerosis Treatment Study (HATS) demonstrated a clinical benefit in coronary artery disease patients with low HDL cholesterol (HDL-C) levels treated with simvastatin and niacin (S-N) or S-N plus antioxidants (S-N+A) compared with antioxidants alone or placebo. Angiographically documented stenosis regress...
journal_title：Journal of lipid research
pub_type： 临床试验,杂志文章
doi：10.1194/jlr.M200439-JLR200
更新日期：2003-04-01 00:00:00
abstract：:Mitochondrial cholesterol is maintained within a narrow range to regulate steroid and oxysterol synthesis and to ensure mitochondrial function. Mitochondria acquire cholesterol through several pathways from different cellular pools. Here we have characterized mitochondrial import of endosomal cholesterol using Chinese...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M029942
更新日期：2012-12-01 00:00:00
abstract：:Whereas antibipolar drug administration to rats reduces brain arachidonic acid turnover, excessive N-methyl-d-aspartate (NMDA) signaling is thought to contribute to bipolar disorder symptoms and may increase arachidonic acid turnover in rat brain phospholipids. To determine whether chronic NMDA would increase brain ar...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M700406-JLR200
更新日期：2008-01-01 00:00:00
abstract：:Immunological tolerance is one of the fundamental aspects of the immune system. The CD4(+)CD25(+) regulatory T (Treg) cells have emerged as key players in the development of tolerance to self and foreign antigens. However, little is known about the endogenous factors and mechanisms controlling their suppressive capaci...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M900101-JLR200
更新日期：2009-12-01 00:00:00
abstract：:Since spheroidal HDL particles (sHDL) are highly dynamic, molecular dynamics (MD) simulations are useful for obtaining structural models. Here we use MD to simulate sHDL with stoichiometries of reconstituted and circulating particles. The hydrophobic effect during simulations rapidly remodels discoidal HDL containing ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M039206
更新日期：2013-10-01 00:00:00
abstract：:Ecdysteroids are potent developmental regulators that control molting, reproduction, and stress response in arthropods. In developing larvae, picogram quantities of individual ecdysteroids and their conjugated forms are present along with milligrams of structural and energy storage lipids. To enhance the specificity a...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.D035949
更新日期：2013-08-01 00:00:00
abstract：:To assess the possible role of altered hepatic processing of free fatty acids in dietary sucrose-induced accumulation of triglyceride in the liver and blood plasma, livers from rats fed commercial laboratory stock and high sucrose diets were perfused both with and without oleic acid substrate. Consumption of the sucro...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
abstract：:Apolipoprotein A-IV (apoA-IV) is involved in the metabolism of chylomicrons and high density lipoproteins. It displays genetic polymorphism due to two co-dominant alleles apoA-IV1 and apoA-IV2. The mutation that causes the polymorphism is a G to T substitution in the third base of codon 360 in the apoA-IV2 allele whic...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1991-03-01 00:00:00
abstract：:Rat lymph chylomicrons were treated with rat heparin-releasable hepatic lipase (HL) or with bovine milk lipoprotein lipase (LPL). The ability of the resulting particles to be taken up by the liver in vivo was assessed following their infusion into the portal vein of partially hepatectomized animals. The following obse...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1988-08-01 00:00:00
abstract：:Glycosylphosphatidylinositols (GPIs) act as membrane anchors of many eukaryotic cell surface proteins. GPIs in various organisms have a common backbone consisting of ethanolamine phosphate (EtNP), three mannoses (Mans), one non-N-acetylated glucosamine, and inositol phospholipid, whose structure is EtNP-6Manα-2Manα-6M...
journal_title：Journal of lipid research
pub_type： 杂志文章,评审
doi：10.1194/jlr.R063313
更新日期：2016-01-01 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：:To study the role of phospholipids in the lipophorin structure, they were removed by phospholipase A2 treatment. Fluorescence lifetimes and accessibility to acrylamide quenching of different diphenylhexatrienyl derivatives, which were used as analogues of the different lipid components, indicate a surface localization...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1996-10-01 00:00:00
abstract：:Loss of function of Niemann-Pick C1 (NPC1) leads to lysosomal free cholesterol storage, resulting in the neurodegenerative disease Niemann-Pick disease type C (NPC). Significant numbers of patients with NPC also suffer from liver disease. Currently, no treatments exist that alter patient outcome, and it is unknown if ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M007211
更新日期：2010-08-01 00:00:00
abstract：:The properties of cholesteryl oleate and triolein in mixed monolayers at the air-water interface have been measured between 24 and 37 degrees C. Analysis of force-area curves obtained as a function of the mol fraction of cholesteryl oleate indicates that at relatively low surface pressures these compounds are miscible...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1978-03-01 00:00:00
