Abstract:
:N-acylethanolamines (NAEs) are a group of lipid mediators synthesized in response to a number of physiological and pathological stimuli. Because of the low tissue concentrations of NAEs, analyses often include liquid extraction followed by solid-phase extraction and subsequent quantitation by LC/MS or GC/MS. Reported levels of NAEs vary considerably, however, and often no explanation is given for these discrepancies. Brought on by difficulties encountered during method development, the effects of using four different brands of silica-containing solid phase extraction (SPE) columns and five different brands of chloroform for sample preparation were investigated. Considerable variation in the retention and recoveries of seven NAEs and 2-arachidonoylglycerol existed between the SPE columns. Furthermore, it was found that some chloroforms contained quantifiable amounts of N-palmitoylethanolamine and N-stearoylethanolamine. Finally, it was found that use of one of the chloroforms resulted in a loss of N-oleoylethanolamine from solution due to addition of chlorine to the ω-9 bond. The identity of this reaction product was confirmed by LC-MS/MS and NMR. It is recommended that these aspects of sample preparation and analysis should be thoroughly validated during method development and the relevant information on specific brands used be reported in future communications in order to better estimate the validity of reported quantitative data.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Skonberg C,Artmann A,Cornett C,Hansen SH,Hansen HSdoi
10.1194/jlr.D004606subject
Has Abstractpub_date
2010-10-01 00:00:00pages
3062-73issue
10eissn
0022-2275issn
1539-7262pii
jlr.D004606journal_volume
51pub_type
杂志文章abstract::In human serum, polymorphism of apoA-II predominantly in HDL3 could be demonstrated. HDL3-apoA-II was composed of four isoproteins, each with a molecular weight of 8600 (reduced form) and identical immunological properties. The isoproteins are designated apoA-II-1 (pI 5.16), apoA-II-2 (pI 4.89) corresponding to the al...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1983-08-01 00:00:00
abstract::We have previously shown that expression of a human apoE cDNA in J774 macrophages enhances cholesterol efflux to HDL3. We have also shown that endogenous apoE expression produces a cell surface pool of apoE associated with proteoglycans. In this series of experiments, we first demonstrate the presence of a cell surfac...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract::Different batches of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) had varying amounts of contaminants which appeared to affect systematic biological studies. This contaminant was separated by silica gel column chromatography followed by high performance liquid chromatography and identified as 1,3-distearoyl-glyce...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1980-01-01 00:00:00
abstract::Glycosylphosphatidylinositol (GPI) enriches GPI-anchored proteins (GPI-AP) in lipid rafts by intimate interaction of its lipid moiety with sphingolipids and cholesterol. In addition to such lipid-lipid interactions, it has been reported that GPI may interact with protein moiety linked to GPI and affect protein conform...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M034421
更新日期:2013-04-01 00:00:00
abstract::At 123 K, crystals of cholesteryl cis-9-hexadecenoate (cholesteryl palmitoleate, C45H74O2) are monoclinic, space group P2(1) with cell dimensions a = 12.917(7), b = 8.910(5), c = 34.04(1) A, beta = 94.95(7) degrees [lambda(CuK alpha) = 1.5424 A] having two independent molecules (A and B) per unit cell. The crystal str...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1984-08-01 00:00:00
abstract::Triacylglycerols (TG) are the major storage form of energy in eukaryotic organisms and are synthesized primarily by acyl CoA:1,2-diacylglycerol acyltransferase (DGAT) enzymes. In vitro DGAT activity has previously been quantified by measuring the incorporation of either radiolabeled fatty acyl CoA or diacylglycerol (D...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D016626
更新日期:2011-09-01 00:00:00
abstract::Lipogenesis in vitro from acetate-1-(14)C was studied in human preputial skin and abdominal skin. Radioactive lipids were separated by column chromatography on Florisil and by thin-layer chromatography on silica gel. Radioactivity was incorporated chiefly into the triglyceride, sterol, and polar lipid fractions, while...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1969-09-01 00:00:00
abstract::Apolipoprotein A-I (apoA-I) induces the translocation of newly synthesized cholesterol as well as caveolin-1 to the cytosolic lipid-protein particle (CLPP) fraction in astrocytes before its appearance in high density lipoprotein generated in the medium (Ito, J., Y. Nagayasu, K. Kato, R. Sato, and S. Yokoyama. 2002. Ap...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M400222-JLR200
更新日期:2004-12-01 00:00:00
abstract::We report the clinical phenotype in three kindreds with familial heterozygous hypobetalipoproteinemia (FHBL) carrying novel truncated apolipoprotein Bs (apoBs) of different sizes (apoB-8.15, apoB-33.4 and apoB-75.7). In D.A. kindred, we found three carriers of a C-deletion in exon 10 leading to the synthesis of apoB-8...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2001-10-01 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::A method has been described for the measurement of apoB concentration and specific activity in very low density lipoprotein (VLDL) and low density lipoprotein (LDL) during metabolic studies. For measurement of specific activity, apoB was separated from other apolipoproteins and lipids by precipitation in, and subseque...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1983-09-01 00:00:00
abstract::Previously, we have shown that lipid-free apoA-I, when incubated with fibroblasts, will produce lipoproteins of pre-alpha mobility (Asztalos, B. F., et al. 1997. Arterioscler. Thromb. Vasc. Biol. 17: 1630-1636). In order to understand the nature of these pre-alpha particles, we further characterized their lipid conten...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1998-08-01 00:00:00
abstract::Expression of constitutively activated Akt in the mammary glands of transgenic mice results in a delay in post-lactational involution. We now report precocious lipid accumulation in the alveolar epithelium of mouse mammary tumor virus-myr-Akt transgenic mice accompanied by a lactation defect that results in a 50% decr...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M300045-JLR200
更新日期:2003-06-01 00:00:00
abstract::The essential fatty acid DHA (22:6, omega-3 or n-3) is enriched in and required for the membrane biogenesis and function of photoreceptor cells (PRC), synapses, mitochondria, etc. of the CNS. PRC DHA becomes an acyl chain at the sn-2 of phosphatidylcholine (PC), amounting to more than 50% of the PRC outer segment phos...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.TR120001137
更新日期:2020-10-26 00:00:00
abstract::The sequences necessary for liver-specific expression of the apolipoprotein (apo) E gene have been shown to reside 3' to the gene, within the apoE/C-I/C-II gene cluster, but have not been precisely characterized. Utilizing a transient transfection reporter gene assay based on the apoC-II promoter, we have localized a ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1993-10-01 00:00:00
abstract::The activity of phospholipase A on phosphatidyl choline and phosphatidal choline spread as monolayers on phosphate buffers containing snake venom (Crotalus atrox or Naja naja) was studied by measuring the fall of surface potential as a function of time, pH, film pressure, temperature, and concentrations of phosphate a...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1966-03-01 00:00:00
abstract::Mammalian spermatogenesis is a complex developmental program in which a diploid progenitor germ cell transforms into highly specialized spermatozoa. One intriguing aspect of sperm production is the dynamic change in membrane lipid composition that occurs throughout spermatogenesis. Cholesterol content, as well as its ...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:10.1194/jlr.R032326
更新日期:2013-01-01 00:00:00
abstract::We have reported the use of a retroviral vector to introduce the low density lipoprotein (LDL) receptor gene into receptor-deficient Watanabe heritable hyperlipidemic (WHHL) rabbit fibroblasts (Miyanohara, A., M. F. Sharkey, D. Steinberg, J. L. Witztum, and T. Friedmann. 1988. Proc. Natl. Acad. Sci. USA. 85: 6538-6542...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1990-12-01 00:00:00
abstract::Lysophospholipid (LP) research has experienced a period of renaissance with the discovery of the lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P) receptors in the late 1990s. Vertebrate LP receptors regulate embryogenesis, vascular development, neurogenesis, uterine development, oocyte survival, immune ce...
journal_title:Journal of lipid research
pub_type: 杂志文章,评审
doi:10.1194/jlr.R800047-JLR200
更新日期:2009-04-01 00:00:00
abstract::Feeding of phytol in large doses (2-5% by weight in the diet) led to accumulation of phytanic acid in the mouse, rat, rabbit, and chinchilla, the degree of accumulation depending upon the level of dietary intake. The relative concentration of phytanic acid, expressed as a percentage of the total fatty acids, was as hi...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1966-09-01 00:00:00
abstract::Serine palmitoyltransferase [EC 2.3.1.50] catalyzes the first unique reaction of sphingolipid biosynthesis. To determine whether or not different rat tissues are capable of initiating this pathway, its activity was determined for microsomes from rat liver, lung, brain, kidney, intestine, spleen, muscle, heart, pancrea...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1985-05-01 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::Acute myeloid leukemia (AML) is the most common acute leukemia in adults. More than half of older AML patients fail to respond to cytotoxic chemotherapy, and most responders relapse with drug-resistant disease. Failure to achieve complete remission can be partly attributed to the drug resistance advantage of AML blast...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M091876
更新日期:2019-06-01 00:00:00
abstract::In the present study, the relative positions of 11 anti-apolipoprotein B monoclonal antibodies have been mapped onto the surface of human low density lipoproteins by electron microscopy. As the epitopes recognized by these antibodies have been previously located on the primary sequence of apoB, these data provide a ma...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1995-09-01 00:00:00
abstract::The polyene antibiotic amphotericin B (AMB) is an effective antifungal agent whose therapeutic potential is limited by poor aqueous solubility and toxicity toward host tissues. Addition of apolipoprotein A-I to a multilamellar phospholipid vesicle dispersion containing 20% (w/w) AMB induces the formation of reconstitu...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D500033-JLR200
更新日期:2006-02-01 00:00:00
abstract::Incubation of ovarian luteal cells with the bioactive lipid mediator lysophosphatidic acid (LPA) for 180 min abolishes gonadotropin-induced steroid production with no attenuation of the cyclic AMP accumulation. Treatment with the lysolipid also diminishes [14C]steroid production in cells preloaded with either [14C]cho...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M400423-JLR200
更新日期:2005-05-01 00:00:00
abstract::The goal of this study was to determine whether apolipoprotein A-I (apoA-I) is lipidated before secretion by HepG2 cells. ApoA-I was extracted from microsomes after radiolabeling with [(35)S]Met/Cys. After ultracentrifugal flotation, d < 1.25 g/ml and d > 1.25 g/ml fractions were immunoprecipitated and analyzed by SDS...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2002-01-01 00:00:00
abstract::Analysis of plasma nonesterified fatty acids (NEFA) by gas-liquid chromatography requires procedures that are both lengthy and cumbersome. A 45-min direct methylation procedure was carried out at 24-29 degrees C on 150 microliter of plasma added with an internal standard in 5.0 ml of methanol-acetyl chloride 50:1 (v/v...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1988-02-01 00:00:00
abstract::In mammals, white adipose tissue (WAT) stores and releases lipids, whereas brown adipose tissue (BAT) oxidizes lipids to fuel thermogenesis. In obese individuals, WAT undergoes profound changes; it expands, becomes dysfunctional, and develops a low-grade inflammatory state. Importantly, BAT content and activity declin...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M079665
更新日期:2018-05-01 00:00:00
abstract::The aim of this study was to investigate the extent to which inflammation is linked with plasma endothelial lipase (EL) concentrations among healthy sedentary men. Plasma C-reactive protein (CRP) concentrations were measured with a highly sensitive commercial immunoassay, plasma interleukin-6 (IL-6) concentrations wer...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.P600002-JLR200
更新日期:2006-12-01 00:00:00