Abstract:
:The extent to which the heart can convert alpha-linolenic acid (alpha-LNA, 18:3n-3) to longer chain n-3 PUFAs is not known. Conversion rates can be measured in vivo using radiolabeled alpha-LNA and a kinetic fatty acid model. [1-(14)C]alpha-LNA was infused intravenously for 5 min in unanesthetized rats that had been fed an n-3 PUFA-adequate [4.6% alpha-LNA, no docosahexaenoic acid (DHA, 22:6n-3)] or n-3 PUFA-deficient diet (0.2% alpha-LNA, nor DHA) for 15 weeks after weaning. Arterial plasma was sampled, as was the heart after high-energy microwaving. Rates of conversion of alpha-LNA to longer chain n-3 PUFAs were low, and DHA was not synthesized at all in the heart. Most alpha-LNA within the heart had been beta-oxidized. In deprived compared with adequate rats, DHA concentrations in plasma and heart were both reduced by >90%, whereas heart and plasma levels of docosapentaenoic acid (DPAn-6, 22:5n-6) were elevated. Dietary deprivation did not affect cardiac mRNA levels of elongase-5 or desaturases Delta6 and Delta5, but elongase-2 mRNA could not be detected. In summary, the rat heart does not synthesize DHA from alpha-LNA, owing to the absence of elongase-2, but must obtain its DHA entirely from plasma. Dietary n-3 PUFA deprivation markedly reduces heart DHA and increases heart DPAn-6, which may make the heart vulnerable to different insults.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Igarashi M,Ma K,Chang L,Bell JM,Rapoport SIdoi
10.1194/jlr.M800093-JLR200subject
Has Abstractpub_date
2008-08-01 00:00:00pages
1735-45issue
8eissn
0022-2275issn
1539-7262pii
M800093-JLR200journal_volume
49pub_type
杂志文章abstract::ATP-binding cassette transporter A1 (ABCA1) plays a crucial role in apoA-I lipidation, a key step in reverse cholesterol transport. cAMP induces apoA-I binding activity and promotes cellular cholesterol efflux. We investigated the role of the cAMP/protein kinase A (PKA) dependent pathway in the regulation of cellular ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.m200235-jlr200
更新日期:2002-12-01 00:00:00
abstract::Nuclear hormone receptors liver X receptor (LXRalpha and LXRbeta) ligands are attractive approaches for the treatment of dyslipidemia and atherosclerosis. To further elucidate the function of LXRalpha in liver lipid metabolism in a disease-relevant animal model, the KKAy mouse, we used adenoviral vectors to selectivel...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M700571-JLR200
更新日期:2009-01-01 00:00:00
abstract::The tear film covers the anterior eye and the precise balance of its various constituting components is critical for maintaining ocular health. The composition of the tear film amphiphilic lipid sublayer, in particular, has largely remained a matter of contention due to the limiting concentrations of these lipid amphi...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M044826
更新日期:2014-02-01 00:00:00
abstract::Recent studies from our laboratory (Yancey, P.G., and R. W. St. Clair. 1992. Arterioscler. Thromb. 12: 1291-1304) have shown that cultured peritoneal macrophages from White Carneau (WC) pigeons clear cholesteryl esters at a slower rate than do macrophages from Show Racer (SR) pigeons (9% per 24 h vs. 42% per 24 h, res...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1994-12-01 00:00:00
abstract::A rapid and accurate method is described for the assay of cholesterol ester hydrolase (CEH) activity. Aliquots of the enzyme-substrate incubation mixture are extracted into isopropanol. The free cholesterol concentration in each extract is determined enzymatically using a single aqueous reagent containing cholesterol ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1978-09-01 00:00:00
abstract::Incubation of 125I-labeled very low density lipoprotein (VLDL) with lipoprotein lipase-rich (postheparin) plasma obtained from intact or supradiaphragmatic rats resulted in the transfer of more than 80% of apoprotein C from VLDL to high density lipoprotein (HDL), whereas apoprotein B was associated with lipoprotein of...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1975-09-01 00:00:00
abstract::Essential fatty acids (EFA) are important structural and functional components of cell membranes. Their deficiency has been associated with several clinical and biochemical abnormalities. In the present study, the lipid profile as well as the concentration, composition, and metabolism of lipoproteins were examined in ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1990-11-01 00:00:00
abstract::Serine palmitoyltransferase (SPT) catalyzes the rate-limiting step of condensation of L-serine and palmitoyl-CoA to form 3-ketodihydrosphingosine (3KDS). Here, we report a HPLC-ESI-MS/MS method to directly quantify 3KDS generated by SPT. With this technique, we were able to detect 3KDS at a level comparable to that of...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D078535
更新日期:2018-01-01 00:00:00
abstract::Boiled coffee contains an unidentified lipid that raises serum cholesterol. We studied the effects of the ingestion of coffee oil fractions of increasing purity in volunteers in order to identify the cholesterol-raising factor. In 15 volunteers who ingested 0.75 g/d of a non-triglyceride-fraction from coffee oil for 4...
journal_title:Journal of lipid research
pub_type: 临床试验,杂志文章,随机对照试验
doi:
更新日期:1994-04-01 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::Subcutaneous fat cells were isolated from genetically obese rats and from rats with obesity produced by hypothalamic lesions. Insulin did not augment the oxidation of fatty acids or their synthesis from glucose-1-(14)C or glucose-1-(3)H by fat cells from either group. Radioactivity from pyruvate-3-(14)C was incorporat...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1968-11-01 00:00:00
abstract::Plasma phospholipid transfer protein (PLTP) is an important regulator of plasma HDL levels and HDL particle distribution. PLTP is present in plasma in two forms, one with high and the other with low phospholipid transfer activity. We have used the human hepatoma cell line, HepG2, as a model to study PLTP secreted from...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M300059-JLR200
更新日期:2003-09-01 00:00:00
abstract::Sterol 27-hydroxylase, the mitochondrial enzyme that catalyzes the first step in oxidation of the sterol side chain in hepatic bile acid synthesis, also catalyzes the synthesis of 27-hydroxycholesterol from cholesterol. We have developed a high performance liquid chromatography (HPLC) assay for this enzyme, using eith...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1993-04-01 00:00:00
abstract::Transcripts encoding a novel member of the lipoprotein receptor superfamily, termed LDL receptor-related protein (Lrp)13, were sequenced from striped bass (Morone saxatilis) and white perch (Morone americana) ovaries. Receptor proteins were purified from perch ovary membranes by protein-affinity chromatography employi...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M050286
更新日期:2014-11-01 00:00:00
abstract::This study has examined the dimeric/oligomeric forms of scavenger receptor class B type I (SR-BI) and its alternatively spliced form, SR-BII, in a diverse group of cells and tissues: i.e., normal and hormonally altered tissues of mice and rats as well as tissues of transgenic animals and genetically altered steroidoge...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M300370-JLR200
更新日期:2004-03-01 00:00:00
abstract::The fatty acid composition of human skin fibroblasts grown in 10% dialyzed fetal calf serum can be modified considerably by adding supplemental fatty acids to the culture medium. The degree of modification was dependent on the concentration of added fatty acid over the range tested, 2.5 X 10(-5) to 1 X 10(-4) M. At th...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1979-05-01 00:00:00
abstract::The surface behavior of a series of cholesteryl esters was studied in mixtures with a model phospholipid, 1-palmitoyl-2-oleoyl phosphatidylcholine. The cholesteryl esters were representative of the predominant forms occurring naturally and qualitative similarities in their phase behavior permits generalization of thei...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1987-09-01 00:00:00
abstract::Nine even-numbered saturated (C4 to C20) and two unsaturated (C18:1, C18:2) cholesterol alkyl ethers were studied by differential scanning calorimetry, polarizing microscopy, and X-ray powder diffraction. Seven of the nine saturated ethers examined melt into stable liquid crystal mesophases. Mesophase transition tempe...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1983-05-01 00:00:00
abstract::Cholesterol 7α-hydroxylase (CYP7A1) is the first and rate-limiting enzyme in the conversion of cholesterol to bile acids in the liver. In addition to absorption and digestion of nutrients, bile acids play a critical role in the regulation of lipid, glucose, and energy homeostasis. We have backcrossed Cyp7a1(-/-) mice ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M064709
更新日期:2016-07-01 00:00:00
abstract::Lipoprotein lipase (LPL) and hepatic lipase (HL) mediate the hydrolysis of triglycerides and phospholipids present in circulating lipoprotein particles and are essential for normal lipid metabolism. Both enzymes have a similar primary amino acid structure and share requirements for intact catalytic, lipid binding, and...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1993-08-01 00:00:00
abstract::The total nitrogen and L-hydroxyproline concentrations of two intra-abdominal and two subcutaneous sites of adipose tissue were measured in male and female Wistar rats. At 100 g body weight the nitrogen concentration of intra-abdominal adipose tissue was slightly lower than that of subcutaneous adipose tissue. As age ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1970-07-01 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::The effect of fat feeding on adipocyte insulin binding was examined to expand a study of adaptive changes in plasma membrane functions. Cells from rats fed a high fat (L) diet for five to seven days bound less insulin and showed a decreased response to insulin (glucose oxidation) compared to those from rats fed a high...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1976-11-01 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::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::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::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::Ceramides play an essential role in modulating immune signaling pathways and proinflammatory cytokine production in response to infectious pathogens, stress stimuli, or chemotherapeutic drugs. In this study, we demonstrated that Aggregatibacter actinomycetemcomitans, the pathogen for aggressive periodontitis, induced ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M031427
更新日期:2013-01-01 00:00:00
abstract::Monolayers of Caco-2 cells, a human enterocyte cell line, were incubated with [1-14C]15-hydroxyeicosatetraenoic acid (15-HETE), a lipid mediator of inflammation, and [1-14C]arachidonic acid. Both fatty acids were taken up readily and metabolized by Caco-2 cells. [1-14C]Arachidonic acid was directly esterified in cellu...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1990-05-01 00:00:00
abstract::Increased plasma concentrations of apolipoprotein A-IV (apoA-IV) in chronic renal disease suggest a metabolic role of the kidney for this antiatherogenic protein. Therefore, we investigated patients with various forms of proteinuria and found increased serum concentrations of apoA-IV in 124 nephrotic patients compared...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M600178-JLR200
更新日期:2006-09-01 00:00:00