Abstract：
:In Refsum disease, disorders of peroxisome biogenesis, and rhizomelic chondrodysplasia punctata, pathological accumulation of phytanic acid results from impaired alpha-oxidation of this branched-chain fatty acid. Previous studies from this laboratory indicated that activation of phytanic acid to its CoA derivative precedes its alpha-oxidation in peroxisomes. It was reported that this reaction is catalyzed by a unique phytanoyl-CoA synthetase in human peroxisomes. We wanted to determine whether phytanic acid activation in rats required long-chain acyl-CoA synthetase (LCS), very long-chain acyl-CoA synthetase (VLCS), or a different enzyme. To test directly whether LCS could activate phytanic acid, rat liver cDNA encoding this enzyme was transcribed and translated in vitro. The expressed enzyme had both LCS activity (assayed with palmitic acid, C16: 0) and phytanoyl-CoA synthetase activity; VLCS activity (assayed with lignoceric acid, C24: 0) was not detectable. The ratio of phytanoyl-CoA synthetized activity to palmitoyl-CoA synthetase activity for LCS synthetized in vitro (approximately 205) was higher than that observed in peroxisomes isolated from rat liver (5-10%), suggesting that the expressed enzyme contained sufficient phytanoyl-Coa synthetase activity to account for all activity observed in intact peroxisomes. Further experiments were carried out to verify that phytanic acid was activated by LCS in rat liver peroxisomes. Attempts to separate LCS from phytanoyl-CoA synthetase by chromatography on several matrices were unsuccessful. Preparative isoelectric focusing revealed that phytanoyl-CoA synthetase and LCS had indistinguishable isoelectric points. Phytanoyl-CoA synthetase activity was inhibited by unlabeled palmitic acid but not by lignoceric acid. Heat treatment inactivated both phytanoyl-CoA and palmitoyl-CoA synthetase activities at similar rates. 5,8,11,14-Eicosatetraynoic acid inhibited activation of phytanic acid and palmitic acid in a parallel dose-dependent manner, whereas activation of lignoceric acid was not affected. These data support our conclusion that rat liver LCS, an enzyme known to be present in peroxisomal membranes, has phytanoyl-CoA synthetase activity.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Watkins PA,Howard AE,Gould SJ,Avigan J,Mihalik SJsubject
Has Abstractpub_date
1996-11-01 00:00:00pages
2288-95issue
11eissn
0022-2275issn
1539-7262journal_volume
37pub_type
杂志文章abstract：:Adipose differentiation-related protein (ADRP) is a lipid droplet-associated protein that is expressed in various tissues. In mice treated with the peroxisome proliferator-activated receptor alpha (PPARalpha) agonist Wy14,643 (Wy), hepatic mRNA and protein levels of ADRP as well as hepatic triglyceride content increas...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M500203-JLR200
更新日期：2006-02-01 00:00:00
abstract：:The measurement of apolipoprotein B (apoB) in purified lipoproteins by immunological assays is subject to criticism because of denatured epitopes or immunoreactivity differences between purified lipoproteins and standard. Chemical methods have therefore been developed, such as the selective precipitation of apoB follo...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：2000-07-01 00:00:00
abstract：:Epoxyeicosatrienoic acids were isolated and purified from female rabbit kidneys. They were identified as a group, prior to resolution, by packed column gas-liquid chromatography-mass spectroscopic techniques as their methyl esters as well as their trimethylsilyl bromohydrin methyl esters. Initial capillary gas-liquid ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1987-07-01 00:00:00
abstract：:The mitochondrial lipids from avocado fruit, cauliflower buds, and potato tubers, and the lipids of chloroplasts isolated from avocado fruit and from cauliflower leaves were identified and the concentrations were determined. The lipid composition was compared with that of beef heart mitochondria. Phospholipids constit...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1973-03-01 00:00:00
abstract：:We have previously observed that the Ya subunit-containing glutathione (GSH) S-transferases from rat liver exhibit a common high affinity binding site for lithocholic acid, bilirubin, and sulfobromophthalein (BSP) (1984. J. Lipid Res. 25: 1177-1183). Subsequently we found that cholic acid and its amidates bound to a s...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1988-03-01 00:00:00
abstract：:The recognition that the 7 alpha-hydroxylation of 27-hydroxycholesterol is catalyzed by an enzyme that is different from cholesterol 7 alpha-hydroxylase raises the question as to the number of similar enzymes that may be present in liver and subserve bile acid synthesis. Thus, both 3 beta-hydroxy-5-cholestenoic acid a...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1996-06-01 00:00:00
abstract：:The accurate quantitation of high density lipoproteins has recently assumed greater importance in view of studies suggesting their negative correlation with coronary heart disease. High density lipoproteins may be estimated by measuring cholesterol in the plasma fraction of d > 1.063 g/ml. A more practical approach is...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1978-01-01 00:00:00
abstract：:Adipocyte triglyceride storage provides a reservoir of energy that allows the organism to survive times of nutrient scarcity, but excessive adiposity has emerged as a health problem in many areas of the world. Monoacylglycerol acyltransferase (MGAT) acylates monoacylglycerol to produce diacylglycerol; the penultimate ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M084947
更新日期：2018-09-01 00:00:00
abstract：:We have developed the technique of rapid (< 2 h) centrifugal ultrafiltration to measure the inter-mixed micellar/vesicular (non-lecithin-associated) bile salt (BS) concentrations (IMC) of individual BS in model biles. This methodology uses a centrifugal concentrator with a reinforced membrane, through which a small fr...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1993-07-01 00:00:00
abstract：:The alpha-naphthylisothiocyanate (ANIT)-treated rat was evaluated as a model for lipoprotein metabolism in cholestatic liver disease. Alterations in lipoprotein composition over a period of 120 h after ANIT treatment (100 mg/kg) were studied. Eighteen hours after treatment, plasma bilirubin and bile acid levels began ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1996-05-01 00:00:00
abstract：:The concentration dependence of the 500 MHz 1H-NMR spectra of taurocholate, taurochenodeoxycholate, taurodeoxycholate, and the monosulfate esters of taurochenodeoxycholate has been examined at 0.154 M NaCl in D2O. The resonances of the C18, C19, and C21 methyl groups and the C23 methylene group are differentially broa...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1992-01-01 00:00:00
abstract：:The hepatic uptake of intravenously injected beta-very low density lipoprotein (beta-VLDL) in rabbits fed 2% (w/w) cholesterol for 3 weeks was investigated. In vitro studies were also conducted to examine the specificity and the capacity of the uptake in isolated liver parenchymal cells. The hepatic uptake of beta-VLD...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1993-04-01 00:00:00
abstract：:Niemann-Pick type C1 disease (NPC1) is an autosomal recessive lysosomal storage disorder characterized by neonatal jaundice, hepatosplenomegaly, and progressive neurodegeneration. The present study provides the lipid profiles, mutations, and corresponding associations with the biochemical phenotype obtained from NPC1 ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.P000331
更新日期：2010-02-01 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：:The density distribution of electronegative LDL [LDL(-)], a cytotoxic and inflammatory fraction of LDL present in plasma, was studied in 10 normolipemic (NL), 6 FH, and 11 hypertriglyceridemic (HTG) subjects. Six LDL subclasses of increased density (LDL1 to LDL6) were isolated by density-gradient ultracentrifugation (...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：2002-05-01 00:00:00
abstract：:After stereospecific oxidation, trimethylsilylated methyl esters of mono- and diunsaturated fatty acids were analyzed by combined gas-liquid chromatography-chemical ionization mass spectrometry. The positions of original double bonds were deduced from the fragment ions produced by the cleavage of the carbon-carbon bon...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1978-02-01 00:00:00
abstract：:In a previously described method for determining the activity of cerebroside galactosidase, the enzyme preparation was incubated with an emulsion of cerebroside which had been labeled in the galactose moiety. The liberated galactose was separated from the emulsion by liquid-liquid partitioning, but the presence of det...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1971-03-01 00:00:00
abstract：:Very few studies have investigated the interrelations between proprotein convertase subtilisin/kexin type 9 (PCSK9) metabolism, cholesterol synthesis, and cholesterol absorption. We aimed to address this issue in a large clinical trial of 245 patients with hypercholesterolemia. Serum lipids, PCSK9, lathosterol (choles...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.P088583
更新日期：2019-01-01 00:00:00
abstract：:Apolipoprotein (apo) E, via its receptor binding domain contained in residues 140-150, mediates hepatic and peripheral tissue binding of cholesterol-rich lipoproteins. Previously, we reported that a synthetic peptide representing a linear tandem repeat of amino acids 141-155, the 141-155 dimer, binds the low density l...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1995-01-01 00:00:00
abstract：:In skin fibroblasts grown from four children with a homozygous form of type II hyperlipoproteinemia, the feedback control of sterol synthesis and the inhibitory effect on hydroxymethylglutaryl (HMG) CoA reductase activity by serum or low density lipoprotein were present, though diminished compared with the effects in ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1975-03-01 00:00:00
abstract：:The mRNA level for cytosolic NADP-dependent isocitrate dehydrogenase (IDH1) increases 2.3-fold, and enzyme activity of NADP-isocitrate dehydrogenase (IDH) 63%, in sterol-deprived HepG2 cells. The mRNA levels of the NADP- and NAD-dependent mitochondrial enzymes show limited or lack of regulation under the same conditio...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M300285-JLR200
更新日期：2003-11-01 00:00:00
abstract：:We designed a rapid method for determining mRNA content of cholesterol biosynthesis enzymes and LDL receptor (LDLR) using a ribonuclease protection assay (RPA). 32P-labeled cRNA fragments for genes of human LDLR and the enzymes HMG-CoA synthase (HMGS), HMG-CoA reductase (HMGR), mevalonate kinase (MK), farnesyl pyropho...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1995-09-01 00:00:00
abstract：:Lipids are used as cellular building blocks and condensed energy stores and also act as signaling molecules. The glycerolipid/ fatty acid cycle, encompassing lipolysis and lipogenesis, generates many lipid signals. Reliable procedures are not available for measuring activities of several lipolytic enzymes for the purp...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.D058438
更新日期：2016-01-01 00:00:00
abstract：:The relationship between overnight postabsorptive (fasting) respiratory exchange ratio (RER) and plasma FFA concentrations was addressed using data from three separate protocols, each of which involved careful control of the antecedent diet. Protocol 1 examined the relationship between fasting RER and the previous day...
journal_title：Journal of lipid research
pub_type： 临床试验,杂志文章
doi：10.1194/jlr.M900021-JLR200
更新日期：2009-09-01 00:00:00
abstract：:The inbred HcB19 mouse strain expresses a truncated form of thioredoxin interacting protein and is phenotypically characterized by fatty liver and elevated plasma triglycerides and VLDL. Recently, these mice have been proposed as an animal model for familial combined hyperlipidemia. The aim of the present study was id...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M400062-JLR200
更新日期：2004-06-01 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
abstract：:We analysed the sensitivity to beta-adrenoceptor agonists in epididymal adipose cells from rats submitted to a stress protocol previously reported to induce alterations in sensitivity to catecholamines in cardiac tissue from rats. Food intake and body weight were lower, whereas adipocytes basal lipolysis was higher (c...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1999-09-01 00:00:00
abstract：:During intestinal absorption amino acids must traverse the lipid-rich epithelial cell membrane, possibly in a lipid-soluble form. In a search for such a form, we have determined the ability of lipid extracted from intestinal mucosa to bind valine. After incubation in a valine-containing medium this lipid (defined as t...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1968-09-01 00:00:00
abstract：:Seven Z-octadecenoic acids having the double bond located in positions 6Z to 13Z were photooxidized. The resulting hydroperoxy-E-octadecenoic acids [HpOME(E)] were resolved by chiral phase-HPLC-MS, and the absolute configurations of the enantiomers were determined by gas chromatographic analysis of diastereoisomeric d...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M018259
更新日期：2011-11-01 00:00:00
abstract：:Familial hypobetalipoproteinemia, a syndrome associated with low plasma cholesterol levels, can be caused by apoB gene mutations. We identified a healthy 42-year-old man whose total plasma cholesterol level was 80 mg/dl. His plasma very low density lipoprotein (VLDL) contained a unique truncated apoB species, apoB-83,...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1992-04-01 00:00:00
