Abstract:
:Recently we evaluated an isotope ratio method (IRM) for measurement of cholesterol absorption in 14 patients (15 experiments) hospitalized in the metabolic ward by comparing it to simultaneous measurements with a fecal radioactivity method (FRM) and found good to excellent agreement between two procedures (Samuel, P., J. R. Crouse, and E. H. Ahrens, Jr. 1978 J. Lipid Res. 19: 82-93). This comparison has now been extended to additional studies carried out in eight hospitalized patients (19 experiments). Of the 34 comparisons between the IRM and the FRM in our hands, 29 were technically acceptable (chromic oxide fecal recovery >/=80%): percent cholesterol absorption was 43.1 +/- 12% by the FRM and 46.0 +/- 11% by the IRM, exhibiting an accuracy within 3.5% at the 95% and 4.7% at the 99% confidence levels. In addition, various procedural modifications of the IRM were studied in out-patients. The measurement of isotope ratios in a single blood sample (analyzed in sextuplicate) on the third day (or later) following the tests gave identical results to those obtained from six to eight daily blood samplings. Blood samples drawn at any time during the day gave cholesterol absorption values similar to those obtained from samples drawn following an overnight fast. Absorption tests carried out before and 1 hr after breakfast, lunch, or dinner, or giving the oral isotope in three divided daily doses all yielded identical results with tests carried out in the am in the fasting state. Cholesterol absorption was markedly reduced when the oral radiolabeled cholesterol was administered in orange juice vs. liquid formula, milk or a solution of glucose and amino acids, consistent with the well-known fact that gallbladder contraction is a critical requirement of cholesterol absorption. A meal high in cholesterol consumed on the day of the test did not influence the results of the absorption measurements. Furthermore, addition of three eggs per day (~750mg cholesterol) for 3 weeks to a low-cholesterol poly-unsaturated fat diet caused no significant change in percent cholesterol absorption in any of eight patients. We conclude that the isotope ratio method accurately and precisely measures cholesterol absorption in man, and that it is suitable not only for in- but also for out-patient studies.-Samuel, P., D. J. McNamara, E. H. Ahrens, Jr., J. R. Crouse, and T. Parker. Further validation of the plasma isotope ratio method for measurement of cholesterol absorption in man.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Samuel P,McNamara DJ,Ahrens EH Jr,Crouse JR,Parker Tsubject
Has Abstractpub_date
1982-03-01 00:00:00pages
480-9issue
3eissn
0022-2275issn
1539-7262journal_volume
23pub_type
杂志文章abstract::In contrast to current methods of bile acid analysis that require the separation of bile acids into different groups prior to their analysis, the HPLC method using a reverse phase column and gradient elution that we developed permits the separation and detection of nonconjugated, glycine-conjugated, and esterified bil...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1997-09-01 00:00:00
abstract::Zinc Finger Protein 202 (ZNF202) is a transcriptional repressor that binds elements found predominantly in genes involved in HDL metabolism. We tested the following hypotheses: 1) frequencies of single-nucleotide polymorphisms (SNPs) and haplotypes in ZNF202 differ between individuals with low and high HDL cholesterol...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M500521-JLR200
更新日期:2006-05-01 00:00:00
abstract::A group of polyunsaturated fatty acids called conjugated linoleic acids (CLAs) are found in ruminant products, where the most common isomers are cis9, trans11 (c 9,t11) and trans10, cis12 (t10,c12) CLA. A crude mixture of these isomers has been shown in animal studies to alter body composition by a reduction in body f...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M300120-JLR200
更新日期:2003-08-01 00:00:00
abstract::23-Nor-deoxycholic acid is widely used as internal standard in gas-liquid chromatographic studies of bile acids. Two batches of this compound, submitted to conventional alkaline hydrolysis of bile acid conjugates, were found to be transformed into a product with chromatographic properties different from those of "auth...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1982-01-01 00:00:00
abstract::Oxidative stress promotes acute kidney injury (AKI). Higher concentrations of HDL cholesterol are associated with less AKI. To test the hypothesis that HDL antioxidant activity is associated with AKI after cardiac surgery, we quantified HDL particle size and number, paraoxonase-1 activity, and isofuran concentrations ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1016/j.jlr.2021.100024
更新日期:2021-01-13 00:00:00
abstract::When NH(4)OH-NH(4)Cl extracts of adipose acetone powder were applied to agarose gel chromatography columns, two peaks of lipoprotein lipase were eluted. The first activity peak (LPL(a)) was eluted with an elution volume of a protein of molecular weight approximately five times that of the second (LPL(b)). Addition of ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1972-01-01 00:00:00
abstract::Dietary fiber is plant-derived material that is resistant to digestion by human alimentary enzymes. Fiber may be divided into two broad chemical classes: 1) non-alpha-glucan polysaccharides (cellulose, hemicelluloses, and pectins) and 2) lignins. Dietary fiber behaves within the gastrointestinal tract as a polymer mat...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:
更新日期:1982-02-01 00:00:00
abstract::The dynamics of human apoE metabolism were explored by examining the effects of alimentary lipemia and postheparin lipolysis on the plasma level and lipoprotein distribution of apoE. In the studies of alimentary lipemia, fasting and postprandial plasma samples were obtained from five normal adult males, each of whom d...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1982-12-01 00:00:00
abstract::This study aimed at measuring the influence of a low salt diet on the development of experimental atherosclerosis in moderately hyperlipidemic mice. Experiments were carried out on LDL receptor (LDLR) knockout (KO) mice, or apolipoprotein E (apoE) KO mice on a low sodium chloride diet (LSD) as compared with a normal s...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M200330-JLR200
更新日期:2003-04-01 00:00:00
abstract::The transcriptional regulation of the rat cholesterol 7 alpha-hydroxylase gene (CYP7) by hormones and signal transduction pathways was studied by transient transfection assay of the promoter activity. HepG2 cells were transfected with deletion mutants of the CYP7 upstream region linked to the luciferase reporter gene....
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1995-11-01 00:00:00
abstract::Initiation of atherosclerosis is characterized by accumulation of aggregates of small lipid droplets and vesicles in the extracellular matrix of the arterial intima. The droplets and vesicles have features that suggest that they are formed from modified plasma-derived low density lipoprotein (LDL) particles. A variety...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:
更新日期:2000-11-01 00:00:00
abstract::Deficiency of lysosomal acid lipase (LAL) leads to either Wolman disease (WD) or the more benign cholesteryl ester storage disease (CESD). To identify the molecular basis of the different phenotypes we have characterised the LAL gene mutations in three new patients with LAL deficiency. A patient with WD was homozygote...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1998-07-01 00:00:00
abstract::HDL subspecies Lp(A-I) and Lp(A-I,A-II) have different anti-atherogenic potentials. To determine the role of lipoprotein lipase (LPL) and hepatic lipase (HL) in regulating these particles, we measured these enzyme activities in 28 healthy subjects with well-controlled Type 1 diabetes, and studied their relationship wi...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M300091-JLR200
更新日期:2003-08-01 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::Low concentrations of oxidized low density lipoprotein (OxLDL) are cytoprotective for phagocytes, although the underlying mechanisms remain unclear. We investigated signaling pathways used by OxLDL to attenuate apoptosis in monocytic cells. OxLDL at 25-50 mug/ml inhibited staurosporine-induced apoptosis in THP-1 cells...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M700100-JLR200
更新日期:2008-01-01 00:00:00
abstract::Plasma levels of HDL cholesterol (HDL-C) have a strong inherited basis with heritability estimates of 40-60%. The well-established inverse relationship between plasma HDL-C levels and the risk of coronary artery disease (CAD) has led to an extensive search for genetic factors influencing HDL-C concentrations. Over the...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:10.1194/jlr.R004739
更新日期:2010-08-01 00:00:00
abstract::Rates of conversion of alpha-linolenic acid (alpha-LNA, 18:3n-3) to docosahexaenoic acid (DHA, 22:6n-3) by the mammalian brain and the brain's ability to upregulate these rates during dietary deprivation of n-3 polyunsaturated fatty acids (PUFAs) are unknown. To answer these questions, we measured conversion coefficie...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M600549-JLR200
更新日期:2007-05-01 00:00:00
abstract::An amino group of phosphatidylethanolamine (PE) is considered as a target for nonenzymatic glycation, and the potential involvement of lipid glycation in the pathogenesis of diabetic complications has generated interest. However, unlike an early glycation product of PE (Amadori-PE), the occurrence and roles of advance...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D004564
更新日期:2010-08-01 00:00:00
abstract::We investigated the role of caveolae in uptake and intracellular trafficking of long chain fatty acids (LCFA) in HepG2 human hepatoma cells. The uptake of [(3)H]oleic acid and [(3)H]stearic acid into HepG2 cells was measured by radioactive assays and internalization of the non-metabolizable fluorescent fatty acid 12-(...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.m100404-jlr200
更新日期:2002-09-01 00:00:00
abstract::Tetradecylthioacetic acid (TTA), which cannot be beta-oxidized, exerts growth-limiting properties in glioma cells. In order to investigate the importance of modulated lipid metabolism and alterations in mitochondrial properties in this cell death process, we incubated glioma cells both with TTA and the oxidizable fatt...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.m200312-jlr200
更新日期:2003-01-01 00:00:00
abstract::A reliable method for purifying envelope-stripped nuclei from immortalized murine embryonic fibroblasts (iMEFs) was established. Quantitative profiling of the glycerophospholipids (GPLs) in envelope-free iMEF nuclei yields several conclusions. First, we find the endonuclear glycerophospholipidome differs from that of ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M068734
更新日期:2016-08-01 00:00:00
abstract::Several different processes involved in the metabolic fate of docosahexaenoic acid (DHA, C22:6n-3) and its precursor in the biosynthesis route, C24:6n-3, were studied. In cultured skin fibroblasts, the oxidation rate of [1-14C] 24:6n-3 was 2.7 times higher than for [1-14C]22:6n-3, whereas [1-14C]22:6n-3 was incorporat...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M300223-JLR200
更新日期:2003-10-01 00:00:00
abstract::We investigated, in the present study, the role of reactive oxygen intermediates (ROI) in the control of macrophage lipoprotein lipase (LPL) secretion. Exposure of murine macrophages to increasing concentrations of hydrogen peroxide (H2O2) resulted in enhanced basal LPL production and mRNA levels. The increase of LPL ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1996-04-01 00:00:00
abstract::Origins of hyperlipidemia and cholestasis that occur during pregnancy were investigated by examining expression of key elements related to plasma and hepatic cholesterol metabolism during pregnancy, lactation, and post-lactation in the rat model. Among major findings were: during pregnancy, the activities of hepatic 3...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1998-11-01 00:00:00
abstract::X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal disorder caused by impaired degradation of very long-chain fatty acids (VLCFAs) due to mutations in the ABCD1 gene responsible for VLCFA transport into peroxisomes. Lorenzo's oil, a 4:1 mixture of glyceryl trioleate and glyceryl trierucate, has been used to reduce...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M044586
更新日期:2014-03-01 00:00:00
abstract::A new genetic variant apolipoprotein (apo), A-I Yame, was discovered during screening for apoA-I genetic variants with isoelectric focusing gel electrophoresis. To investigate the structural abnormality of apoA-I Yame, we amplified the apoA-I gene isolated from the proband's peripheral blood leukocytes with the polyme...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1991-08-01 00:00:00
abstract::Lipoproteins internalized by the LDL receptor (LDLR) are released from this receptor in endosomes through a process that involves acid-dependent conformational changes in the receptor ectodomain. How acidic pH promotes this release process is not well understood. Here, we assessed roles for six histidine residues for ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M070938
更新日期:2017-02-01 00:00:00
abstract::The acylation of glycerol-3-phosphate by acyl-CoA is regarded as the first committed step for the synthesis of the lipoidal moiety in glycerolipids. The direct acylation of glycerol in mammalian tissues has not been demonstrated. In this study, lipid biosynthesis in myoblasts and hepatocytes was reassessed by conducti...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2001-12-01 00:00:00
abstract::The inbred C57L strain but not the AKR strain of mice carry Lith genes that determine cholesterol gallstone susceptibility. When C57L mice are fed a lithogenic diet containing 15% fat, 1% cholesterol, and 0.5% cholic acid, gallbladder bile displays rapid cholesterol supersaturation, mucin gel accumulation, increases i...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-11-01 00:00:00
abstract::In breast cancer, 17β-estradiol (E2) plays critical roles mainly by binding to its canonical receptor, estrogen receptor (ER) α66, and eliciting genomic effects. E2 also triggers rapid, nongenomic responses. E2 activates sphingosine kinase 1 (SphK1), increasing sphingosine-1-phosphate (S1P) that binds to its receptors...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M085191
更新日期:2018-12-01 00:00:00