Abstract:
:Cyclophosphamide injection into the fasted rabbit induces a hypertriglyceridemia (4.6 mM vs. 0.8 mM in controls) and a defect of lipoprotein lipase (LPL), as measured in post-heparin plasma (PHP). In contrast, administration of the drug into fed animals tends to increase PHP-LPL. The effects of cyclophosphamide on LPL activity and synthesis, depending on the nutritional state, were thus studied in two sites: periepididymal adipose tissue and heart. In adipose tissue, fasting decreased LPL activity to 45.2 mIU/g (P < 0.001) compared to 667.9 mIU/g in fed animals. PHP-LPL activity was also decreased by 45% upon starvation. These modulations appeared to be related to plasma insulin levels. The relative rate of synthesis of fat tissue LPL was decreased from 0.32% total protein synthesis in fed animals to 0.10% in fasted rabbits, concordant with a reduction in the expression of LPL specific mRNA. Cyclophosphamide administration to the fed rabbit led to decreases of LPL activity and synthesis in the adipose tissue, similar to those observed upon starvation. However, when injected into fasted animals, the drug did not further depress fat tissue LPL. Fasting did not change heart LPL activity (288.3 mIU/g vs. 239.3 in fed animals) nor its relative rate of synthesis (0.21% of total protein synthesis). However, cyclophosphamide induced opposite effects, depending on the nutritional state: after injection into fed animals, heart LPL activity increased up to 477.2 mIU/g (P < 0.01) with a concomitant increase in the LPL synthesis rate. Conversely, drug administration into fasted rabbits led to a decrease of heart LPL activity to 133.9 mIU/g. Similar qualitative variations were recorded in postheparin plasma. Hence, although insensitive to nutritional modulations, heart LPL responded differently to cyclophosphamide, depending on the nutritional state. In spite of those different modulations of heart and adipose tissue LPL, the enzyme isolated from these two sources displayed similar molecular mass, immunoreactivity, and catalytic properties. The effects of cyclophosphamide injection on very low density lipoprotein (VLDL)-triacylglycerol (TG) synthesis were also investigated, as a possible determinant of hypertriglyceridemia. The drug stimulated TG synthesis in both nutritional states, and maximally by 45% in fed animals. Hence, a defect of heart and postheparin plasma LPL appears as a major determinant of hypertriglyceridemia in cyclophosphamide-treated fasted rabbits.(ABSTRACT TRUNCATED AT 400 WORDS)
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Lespine A,Azema C,Gafvels M,Manent J,Dousset N,Chap H,Perret Bsubject
Has Abstractpub_date
1993-01-01 00:00:00pages
23-36issue
1eissn
0022-2275issn
1539-7262journal_volume
34pub_type
杂志文章abstract::Adipose tissue was shown to contain 0.6-1.6 mg of cholesterol per gram wet weight. When expressed per unit of protein or organ mass, fat tissue contains more cholesterol than most other organs or membranes. The cholesterol content of fat tissue increased with the age and weight of the rat. Over 95% of adipose tissue s...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1973-05-01 00:00:00
abstract::Interactions of apolipoprotein A-I (apoA-I) with cell membranes appear to be important in the initial steps of reverse cholesterol transport. The objective of this work was to examine the effect of three distinct conformations of apoA-I (lipid-free and in 78 A or 96 A reconstituted high density lipoproteins, rHDL) on ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:2002-02-01 00:00:00
abstract::Investigations of the topography of glycerolipid synthetic enzymes within the transverse plane of microsomal vesicles indicated an exclusive cytoplasmic surface location of active sites. Evidence was derived from studies employing proteases and other impermeant inhibitors, from investigations of latency and substrate ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1981-03-01 00:00:00
abstract::Long-chain polyunsaturated fatty acids (PUFA) orchestrate immunity and inflammation through their capacity to be converted to potent inflammatory mediators. We assessed associations of FADS gene cluster polymorphisms and fasting serum PUFA concentrations in a fully ascertained, geographically isolated founder populati...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M008359
更新日期:2010-09-01 00:00:00
abstract::The extent of hypercholesterolemia varies considerably in patients with familial hypercholesterolemia (FH). We hypothesized that the variability of the FH phenotype might be partly explained by variation in proprotein convertase subtilisin kexin type 9 (PCSK9) activity. Individuals between 18 and 53 years of age who h...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.P023994
更新日期:2012-05-01 00:00:00
abstract::Three pentadecynoic acids, with the triple bond in the 8-, 9-, and 10-positions, have been synthesized on a gram scale in over-all yield of 65% by refinements of the five-step Ahmad-Strong method; isolation of intermediates was shown to be unnecessary prior to purification of the acetylenic nitriles by column chromato...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1969-11-01 00:00:00
abstract::Adipose tissue contains one of the largest reservoirs of cholesterol in the body. Adipocyte dysfunction in obesity is associated with intracellular cholesterol accumulation, and alterations in cholesterol homeostasis have been shown to alter glucose metabolism in cultured adipocytes. ABCA1 plays a major role in choles...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M045294
更新日期:2014-03-01 00:00:00
abstract::Niemann-Pick disease, type C (NP-C), often associated with Niemann-Pick disease, type C1 (NPC1) mutations, is a cholesterol-storage disorder characterized by cellular lipid accumulation, neurodegeneration, and reduced steroid production. To study NPC1 function in vivo, we cloned zebrafish npc1 and analyzed its gene ex...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M012377
更新日期:2011-07-01 00:00:00
abstract::Remnant-like emulsions were prepared with lipid compositions similar to remnants derived from triacylglycerol-rich lipoproteins. When injected into the bloodstream of conscious mice the remnant-like emulsions labeled with cholesteryl[13C]oleate were metabolized in the liver and the appearance of 13CO2 in the breath wa...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1998-03-01 00:00:00
abstract::The apoE gene exhibits two common polymorphisms that have been associated with both coronary artery disease and Alzheimer's disease. The polymorphisms create the three allelic isoforms E2, E3, and E4 which are encoded by Cys;-Cys, Cys;-Arg, and Arg;-Arg at amino acid positions 112 and 158, respectively. Numerous metho...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract::The concentration of cholesterol carried in low density lipoproteins (LDL-C) is primarily determined by the rate at which LDL-C is produced (Jt) and the rate at which the liver takes up this particle through receptor-dependent transport (Jm). The accumulation of specific dietary fatty acids in the liver profoundly alt...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1994-09-01 00:00:00
abstract::We previously have shown that LDL-R354, a truncated low density lipoprotein (LDL) receptor, is a calcium binding protein. LDL-R354 is composed of the ligand binding domain and repeat A of the EGF precursor homology domain of the full-length human LDL receptor. We also found that Ca2+ was required for the interaction b...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1998-02-01 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::Achilles tendon xanthomas are associated with increased cardiovascular risk in patients with familial hypercholesterolemia (FH). Oxidized low density lipoprotein (OxLDL), the antibodies against OxLDL, and the LDL-associated phospholipase A(2) (Lp-PLA(2)) may play important roles in atherogenesis. We investigated the p...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M600109-JLR200
更新日期:2006-10-01 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::The activities of hepatic fatty acid oxidation enzymes in rats fed perilla oil rich in alpha-linolenic acid (alpha-18:3) were compared with those fed saturated fats or safflower oil (the mixture of safflower oil and olive oil, 94:8, w/w) containing the same amount of polyunsaturated fatty acids with perilla oil exclus...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1996-03-01 00:00:00
abstract::Cerebrosides containing either threo- or erythro-[3-3-H]sphingosine were synthesized by a new procedure. Glucopyranosyl or galactopyranosyl ceramides were converted to their 3-keto derivatives with 2,3-dichloro-5,6-dicyanobenzoquinone and reduced with 3-H-labeled sodium borohydride. The resulting tritiated cerebroside...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1975-07-01 00:00:00
abstract::Liver and kidney microsomes have been found to catalyze a rapid decarboxylation of retinoic acid in vitro. The reaction requires NADPH and Fe(2+), and is further stimulated by the presence of pyrophosphate. Thiamine pyrophosphate contained sufficient iron as an impurity to provide strong enhancement of the reaction in...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1968-07-01 00:00:00
abstract::In mammals, vitamin A is primarily stored as retinyl esters in hepatic stellate cells under normal dietary intake of the vitamin. Previously, extrahepatic vitamin A-storing stellate cells have only been identified in animals maintained on a vitamin A-rich diet, and it has not been known whether these cells play a role...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1997-04-01 00:00:00
abstract::A reproducible cell culture system is described that allows the study of adipose conversion in fibroblast-like cells isolated by collagenase digestion of epididymal and perirenal adipose tissue from male rats weighing 70-200 g. Adipose conversion as measured by lipid accumulation and increase in glycerophosphate dehyd...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1987-06-01 00:00:00
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 ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.D004606
更新日期:2010-10-01 00:00:00
abstract::In vitro, -polylysine (EPL) strongly inhibited the hydrolysis of trioleoylglycerol emulsified with phosphatidylcholine (PC) and taurocholate by either pancreatic lipase or carboxylester lipase. The EPL concentration required for 50% inhibition of pancreatic lipase, 0.12 microM, was eight times lower than the concentra...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M600168-JLR200
更新日期:2006-08-01 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::The early premalignant liver provides a model in which to study metabolic alterations that may be permissive for the development of full malignancy. Although there are biochemical changes in this model, there are no detectable morphological ones when compared with a normal, fully differentiated liver. The maintenance ...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1990-05-01 00:00:00
abstract::Three 14C-labeled 22-carbon polyunsaturated fatty acids, 7,10,13,16-[14C]docosatetraenoic acid (22:4(n-6)), 7,10,13,16,19-[14C]docosapentaenoic acid (22:5(n-3)), and 4,7,10,13,16,19-[14C]docosahexaenoic acid (22:6(n-3)), were compared with [3H]arachidonic acid (20:4(n-6] and [14C]linoleic acid (18:2(n-6)) to character...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1986-11-01 00:00:00
abstract::In mammals, the apolipoprotein (apo) A-I gene is expressed predominantly in liver and intestine, while in avian species it is expressed in all tissues. Although liver and intestine are the major sites of chicken apoA-I mRNA synthesis, there are appreciable amounts of apoA-I mRNA in kidney, ovary/testes, brain, lung, s...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1992-06-01 00:00:00
abstract::HDL plays crucial roles at multiple stages of the pathogenesis of atherosclerosis. AMP-activated protein kinase (AMPK) is a therapeutic candidate for the treatment of cardiovascular disease. However, the effect of AMPK activation on HDL functionality has not been established in vivo. We assessed the effects of pharmac...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M073270
更新日期:2017-08-01 00:00:00
abstract::Selenocysteine (Sec) insertion sequence-binding protein 2 (SBP2) is essential for the biosynthesis of Sec-containing proteins, termed selenoproteins. Subjects with mutations in the SBP2 gene have decreased levels of several selenoproteins, resulting in a complex phenotype. Selenoproteins play a significant role in ant...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:10.1194/jlr.M059105
更新日期:2015-11-01 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::A method for the preparation of 1-alkyl 2-acyl glycero-3-phosphorylcholine, labeled in the 2-position with oleic acid-1-(14)C is described. This method, based on the acylation of a 1-alkyl glycero-3-phosphorylcholine-CdCl(2) complex which is, in turn, formed from 1-alk-1-enyl glycero-3-phosphorylcholine by hydrogenati...
journal_title:Journal of lipid research
pub_type: 杂志文章
doi:
更新日期:1970-09-01 00:00:00