Abstract:
:Conventional ideas concerning the unidirectional movement of triacylglycerol from intestinal lumen to lymph with sn-2-monoacylglycerol being the major glyceride-glycerol precursor were challenged by our finding that steady state specific activities of radiolabeled triacylglycerol (glyceryl moiety) in the intestinal mucosa and lumen were greatly reduced as compared to the specific activity of intraduodenally infused triacylglycerol. Investigation of the point at which the radiolabel was diluted was performed in mesenteric lymph duct-cannulated rats with a duodenal cannula through which trioleoyl[3H]glycerol was constantly infused. Both within the bowel lumen and in the intestinal mucosa, monoacylglycerol, diacylglycerol, and triacylglycerol specific activities were 31% or less of the specific activity of the infusate; chylomicron triacylglycerol specific activity was 75%. Efflux of neutral lipid from the mucosa into the bowel lumen was directly demonstrated by finding that when 3H glucose was injected intraperitoneally during triolein infusion, luminal triacylglycerol had a higher specific activity than was present in the mucosa. We conclude that there are two pools of mucosal triacylglycerol. One is rapidly transported and derives most of its glyceride-glycerol from luminal monoacylglycerol. The second is slowly transported; it derives its glyceride-glycerol mainly from endogenous sources and may efflux back into the bowel lumen.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Mansbach CM 2nd,Parthasarathy Ssubject
Has Abstractpub_date
1982-09-01 00:00:00pages
1009-19issue
7eissn
0022-2275issn
1539-7262journal_volume
23pub_type
杂志文章abstract::Genetic defects in SAR1B GTPase inhibit chylomicron (CM) trafficking to the Golgi and result in a huge intraenterocyte lipid accumulation with a failure to release CMs and liposoluble vitamins into the blood circulation. The central aim of this study is to test the hypothesis that SAR1B deletion (SAR1B-/- ) disturbs e...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.RA119000119
更新日期:2019-10-01 00:00:00
abstract::The objective of this study was to investigate the mobilization of individual fatty acids from human subcutaneous adipose tissue in vivo. Concentrations of individual non-esterified fatty acids were measured in arterialized plasma and in the venous drainage from subcutaneous abdominal adipose tissue in eight normal su...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1996-09-01 00:00:00
abstract::The Delta6-desaturase catalyzes key steps in long-chain polyunsaturated fatty acid biosynthesis. Although the gene coding for this enzyme has been isolated in diverse animal species, the protein structure remains poorly characterized. In this work, rat Delta6-desaturase expressed in COS-7 cells was shown to localize i...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M300339-JLR200
更新日期:2004-01-01 00:00:00
abstract::The rate-limiting step in the transit of dietary fat across the intestinal absorptive cell is its exit from the endoplasmic reticulum (ER) in a specialized ER-to-Golgi transport vesicle, the prechylomicron transport vesicle (PCTV). PCTV bud off from the ER membranes and have unique features; they are the largest ER-de...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M002758
更新日期:2010-05-01 00:00:00
abstract::Acetyl-L-carnitine is known as a reservoir of activated acetyl units and as a modulator of metabolic function. The objective of this study was to quantify the fate of the acetyl moiety of acetyl-L-carnitine in lipogenic pathways. Lipogenesis was studied in an adipocyte model, differentiated 3T3-L1 cells, and a hepatom...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1997-07-01 00:00:00
abstract::We have shown previously that low density lipoprotein (LDL) subjected to vortexing forms self-aggregates that are avidly phagocytosed by macrophages. That phagocytic uptake is mediated by the LDL receptor. We now show that LDL self-aggregation is strongly inhibited (80-95%) by the presence of high density lipoprotein ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1990-04-01 00:00:00
abstract::A modification of the semiautomated assay method of Antonis (1965. J. Lipid Res. 6:307-312) for free fatty acid is presented. Free fatty acids are extracted from serum or plasma into di-n-butyl ether-2-methoxyethanol; the extract is almost free from phospholipids. The acids are analyzed in a portion of extract by a co...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1978-02-01 00:00:00
abstract::Lecithin:cholesterol acyltransferase (LCAT) deficiency syndromes represent a group of rare genetic disorders of HDL metabolism that have been the subject of a large number of clinical, biochemical, and genetic studies. Of special interest are patients with LCAT-related disorders with severe HDL deficiency and the appa...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:
更新日期:1997-02-01 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::A positive effect of all-trans retinoic acid (ATRA) on white adipose tissue (WAT) oxidative and thermogenic capacity has been described and linked to an in vivo fat-lowering effect of ATRA in mice. However, little is known about the effects of ATRA on mitochondria in white fat. Our objective has been to characterize t...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M053652
更新日期:2015-06-01 00:00:00
abstract::The isolated perfused rat liver was used to study the 300-800 A electron-opaque bodies which had previously been described in the liver cell Golgi apparatus, smooth endoplasmic reticulum, and space of Disse. When the perfusion medium was enriched with linoleate, the number and electron opacity of these particles incre...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1967-09-01 00:00:00
abstract::Bile acids play important roles in the regulation of lipid, glucose, and energy homeostasis. Recent studies suggest that glucose regulates gene transcription in the liver. The aim of this study was to investigate the potential role of glucose in regulation of bile acid synthesis in human hepatocytes. High glucose stim...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M002782
更新日期:2010-04-01 00:00:00
abstract::The chemical and biochemical properties of cholesterol-enriched and cholesterol-poor chylomicrons from rat lymph have been compared. The enriched particles, prepared from cholesterol-containing lipid dispersions, passed into the duodenum, had four to ten times the cholesteryl ester content of the control chylomicrons ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1978-08-01 00:00:00
abstract::Plasma free fatty acid (FFA) transport in human subjects has been studied during the course of prolonged ingestion of different amounts of glucose. Compared with the fasting state, hypocaloric glucose intake resulted in marked suppression of net transport of FFA with no change in (fractional) turnover rate. There was ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1972-07-01 00:00:00
abstract::Recombinant human pancreatic lipase-related protein 2 (rHPLRP2) was produced in the protease A-deficient yeast Pichia pastoris. A major protein with a molecular mass of 50 kDa was purified from the culture medium using SP-Sepharose and Mono Q chromatography. The protein was found to be highly sensitive to the proteoly...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M600486-JLR200
更新日期:2007-07-01 00:00:00
abstract::Sphingolipids (SLs) have been implicated in numerous important cellular biologies; however, their study has been hindered by the complexities of SL metabolism. Furthermore, enzymes of SL metabolism represent a dynamic and interconnected network in which one metabolite can be transformed into other bioactive SLs throug...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M089714
更新日期:2019-04-01 00:00:00
abstract::A method has been developed for rapidly quantitating the cholesterol concentration of normal and certain variant lipoproteins in a large number of patients (over 240 in one week). The method employs a microcomputer interfaced to the vertical autoprofiler (VAP) described earlier (Chung et al. 1981. J. Lipid Res. 22: 10...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1982-08-01 00:00:00
abstract::The characteristics of 7 alpha-dehydroxylase, a bile acid-biotransforming enzyme, were determined using dialyzed cell extracts of Eubacterium sp. V.P.I. 12708. 7 alpha-Dehydroxylase was induced by cholic acid in this organism. Induction by cholic acid resulted in the differential synthesis of at least five new polypep...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1981-08-01 00:00:00
abstract::Rat spermatogenic cells contain sphingomyelins (SMs) and ceramides (Cers) with very long-chain PUFAs (VLCPUFAs) in nonhydroxylated (n-V) and 2-hydroxylated (h-V) forms. How these atypical species distribute among membrane fractions during differentiation was investigated here using a detergent-free procedure to isolat...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M072595
更新日期:2017-03-01 00:00:00
abstract::Biosynthetic pathways of phosphatidylcholine and triglyceride were studied in proliferating hepatic endoplasmic reticulum of rats pretreated with phenobarbital. Phosphatidylcholine accounted for the major increment in membrane phospholipid. In vitro measurements of hepatic microsomal enzymes which catalyze phosphatidy...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1971-01-01 00:00:00
abstract::Serum amyloid A (SAA) is an acute phase reactant that can become the predominant apolipoprotein of high density lipoprotein (HDL) during severe inflammatory states. However, the function of SAA is unknown. To study the ability of SAA to form HDL in the absence of apolipoprotein A-I, we expressed the mouse SAA pI 6.15 ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1997-08-01 00:00:00
abstract::The implication of cholesteryl ester transfer protein (CETP) in the high density lipoprotein (HDL) conversion process was studied by incubating HDL3 with a purified CETP preparation for 24 h at 37 degrees C. At a physiological plasma level, CETP induced a decrease of the HDL3 fraction (8.6 nm diameter) and the appeara...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1990-09-01 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
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::Trihydroxyoctadecenoic acids (TriHOMEs) are linoleic acid-derived oxylipins with potential physiological relevance in inflammatory processes as well as in maintaining an intact skin barrier. Due to the high number of possible TriHOME isomers with only subtle differences in their physicochemical properties, the stereoc...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D087429
更新日期:2018-10-01 00:00:00
abstract::Monospecific antisera were produced to two chylomicron apoproteins (apoB, apoA-I) and utilized for indirect immunofluorescent localization of these apoproteins within rat intestinal epithelium during normal and impaired lipid absorption. Isolated intestinal epithelial cells prepared after different periods of lipid ab...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1978-02-01 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 pathogenesis of aortic valve stenosis (AS) is characterized by the accumulation of LDL-derived cholesterol in the diseased valves. Since LDL particles also contain plant sterols, we investigated whether plant sterols accumulate in aortic valve lesions. Serum samples were collected from 82 patients with severe AS a...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M800058-JLR200
更新日期:2008-07-01 00:00:00
abstract::Acyl-CoA-dependent O-acyltransferases catalyze reactions in which fatty acyl-CoAs are joined to acyl acceptors containing free hydroxyl groups to produce neutral lipids. In this report, we characterize a human multifunctional O-acyltransferase (designated MFAT) that belongs to the acyl-CoA:diacylglycerol acyltransfera...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M500168-JLR200
更新日期:2005-11-01 00:00:00
abstract::The effects of eicosapentaenoic acid and oleic acid on lipid synthesis and secretion by HepG2 cells were examined to identify fatty acid specific changes in lipid metabolism that might indicate a basis for the hypolipidemic effect attributed to eicosapentaenoic acid and related n-3 fatty acids. Cellular glycerolipid s...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1991-02-01 00:00:00