bluuebunny/crossref_metadata_2025 huggingface dataset:
On the levels of alkyl and alk‐1‐enyl glycerolipids in normal and neoplastic tissues: A method of quantification
Authors: Su Kwei Lee , Schmid Harald H. O.
Published: November 2006

A method is described for the quantification of the constituentO‐alkyl andO‐alk‐1‐enyl glycerols of neutral lipids or phospholipids. The method involves chemical degradation, the preparation of derivatives, and quantification by gas chromatography using internal standards. Alk‐1‐enyl moieties are converted to alkyl substituted dioxanes in the presence of 1,1‐dimethoxyheptadecane as standard; alkyl glycerols are analyzed as isopropylidene derivatives using 1‐O‐heptadecyl glycerol as internal standard. The method is applied to the quantification of alkyl and alk‐1‐enyl glycerols derived from total lipids of rat heart, liver, testes, and brain and of various transplantable tumors, i.e. amelanotic melanoma, melanoma B16, sarcoma T241, and Novikoff hepatoma. The levels of alkyl glycerols range from 0.11–1.07% total lipids and those of alk‐1‐enyl glycerols from 0.49–5.03%. The data are compared to those obtained by other methods.
Slow exchange of erythrocyte and plasma phospholipids
Authors: Calvert G. D. , Scott P. J.
Published: November 2006

32P‐Orthophosphate was injected intravenously into a pig, and the specific activities of serum phospholipids and phosphatidylcholine, serum and urine inorganic phosphorus, and erythrocyte phospholipids were followed for the next eight days. The specific activities of serum phospholipids, phosphatidylcholine, and inorganic phosphorus declined monoexponentially and were not significantly different from each other after the first day. These data imply that there are no large poorly labeled pools of inorganic phosphorus or phospholipids supplying serum phospholipid. Phospholipid metabolism is sufficiently rapid to obscure any immediate precursor product relationship. The specific activity of erthrocyte phospholipid rose slowly to a maximum on ca. the fourth day. The data were consistent with a precursor product relationship between serum phospholipids and part of the erythrocyte phospholipids.
Ethanolamine kinase activity and compositions of diacylglycerols, phosphatidylcholines and phosphatidylethanolamines in livers of choline‐deficient rats
Authors: Tinoco J. , Endemann G. , Medwadowski B. , Miljanich P. , Williams M. A.
Published: November 2006

These experiments were performed to find the reasons for the increased concentrations of docosahexaenoyl phosphatidylethanolamines (PE) in livers of choline‐deficient rats. We measured the activity of ethanolamine kinase, which catalyzes the first step in PE formation. We also measured the compositions of PE and phosphatidylcholines (PC) and concentrations and fatty acid compositions of diacylglycerols (DG), which are precursors of PE. Young male rats were fed for one week a low‐methionine, choline‐deficient diet, or the same diet supplemented with choline. Ethanolamine kinase activity was measured in liver cytosol (100,000 g supernatant). Fatty acids were measured in total liver diacylglycerols and in microsomal PE and PC. Ethanolamine kinase activities were equal in choline‐deficient and choline‐supplemented rats. Concentrations of DG were elevated 6‐fold by choline deficiency. The percentage of docosahexaenoic acid (22∶6n−3) in microsomal PE was nearly doubled by choline deficiency. Although the increased concentrations of PE in choline‐deficient livers cannot be attributed to increased activity of ethanolamine kinase, the rate of PE formation probably was increased by increases in concentrations of its precursors, including DG. The disproportionate increase in 22∶6n−3 PE probably was caused by a selective formation of PE from DG that contain 22∶6n−3.
The lipid composition of erythrocytes in european cattle and buffalo steers
Authors: O'Kelly J. C. , Mills S. C.
Published: November 2006

This study compared the lipid composition of the red blood cells of European cattle and of buffalo steers at the same level of feed intake in a thermoneutral evironment. The mean volumes of the erythrocytes and their lipid content were greater in buffalo than those in cattle. However, the amounts of phospholipid and cholesterol in cells of equal volume were higher in buffalo than in cattle. In contrast, the phospholipid level at a given cholesterol level was higher in cattle than in buffalo. The distribution of the different molecular species of phospholipids in the red cells of the two breeds were similar, but there were significant distinctions in their fatty acid patterns, notably in the levels of 24∶0 and 24∶1 in the sphingomyelin fractions. The proportion of total monounsaturated acids in the erythrocytes were similar from both breeds. However, there was a higher percentage of polyunsaturated fatty acids with a corresponding lower content of total saturated fatty acids in the red cells from buffalo than in those from cattle. The breed differences in erythrocyte lipid composition are discussed in relation to breed differences in red cell characters and could lead to a better understanding of the mechanisms of environmental adaptation.
Volatile hydrocarbon and carbonyl products of lipid peroxidation: A comparison of pentane, ethane, hexanal, and acetone as in vivo indices
Authors: Dillard Cora J. , Tappel Al L.
Published: November 2006

A study was undertaken to determine whether respiratory hexanal and acetone as well as pentane and ethane could be measured as potential indices of lipid peroxidation in vivo. The tests of induction of lipid peroxidation in rats included injection of iron‐dextran and the vitamin E deficiency status. Injection of 460 mg of iron/100 g body wt over a 28‐day period increased pentane and ethane production 4‐ and 6‐fold, respectively. Hexanal production was increased 7‐fold after injection of 60 mg of iron/100 g body wt, and then it fell back to the preinjection level in spite of continued injection of iron‐dextran. Acetone production was lower in iron‐injected rats than in controls, and it was ca. 10‐fold higher in fasted vitamin E‐deficient rats than in vitamin E‐supplemented rats, being ca 48 and 5 nmol/100 g/min, respectively. It was observed that halomethane injection did not increase hexanal production, while acetone and pentane production were increased. Pentane and hexanal, but not acetone, were found to arise from decomposition of linoleic acid hydroperoxide in vitro. It was concluded that hydrocarbon gases are better indices of lipid peroxidation than hexanal, which is enzymatically metabolized, and acetone, the production of which is dominated by factors such as altered carbohydrate metabolism.
Effect of estrogen on fatty acid synthetase in the chicken oviduct and liver
Authors: Aprahamian Simon , Arslanian Michael J. , Stoops James K.
Published: November 2006

Estrogen administered to one‐month‐old female chickens resulted in a 180‐fold increase in the amount of fatty acid synthetase, a seven‐fold increase in the enzyme activity per gram of tissue and a 25‐fold increase in the weight of the oviduct. In contrast, the fatty acid synthetase content in liver increased three‐fold; activity per gram of tissue increased two‐fold and the weight increased two‐fold. The alrge increase in the fatty acid synthetase activity in the oviduct was due to a corresponding increase in the amount of the fatty acid synthetase protein since the specific activities of highly purified preparations of oviduct and liver fatty acid synthetases were the same and the two enzymes had the same end point as determined by immunoprecipitation. That the increase in activity of the oviduct enzyme is not due to a modification was further supported by physicochemical comparison of the oviduct enzyme with the chicken liver enzyme. Thus, the synthetase complexes have similar size, their subunit composition and size appear to be the same, and both are multifunctional enzymes. Finally, kinetic studies and product analyses indicated no catalytic difference between the enzyme induced by estrogen in the oviduct and the liver enzyme.
The effect of hibernation on the positional distribution of ethanolamineglycerophospholipid fatty acids in hamster brain membranes
Authors: Blaker William D. , Moscatelli Ezio A.
Published: November 2006

Microsomal and myelin membrane fractions were prepared from the brains of warm‐adapted (room temperature) and hibernating Syrian Hamsters (Mesocricetus auratus). Ethanolamineglycerophospholipids were isolated and subjected to a fraction scheme to separate the fatty acids of the plasmenylethanolamine and the phosphatidylethanolamine 1 and 2 positions. The major changes in microsomal phosphatidylethanolamine with hibernation were relative increases in 18∶1 at the 1 position and 20∶4(n−6) in the 2 position. In myelin, 18∶1 increased and 18∶0 decreased at the 1 position while the 2 position showed an increase in 16∶0 and a decrease in 22∶6(n−3). Plasmenylethanolamine fatty acids also changed in microsomes and myelin although the magnitudes were not as great and confined to longer chain fatty acids. In both membranes, fatty acid alterations were position‐specific, and no new types of fatty acids were introduced at any position.
Long chain phenols: Part XI. Composition of natural cashew nutshell liquid (Anacardium occidentale) from various sources
Authors: Tyman John H. , Kiong Lam Soot
Published: November 2006

The composition of cashew nutsAnacardium occidentale from different terrestrial sources has been studied. Samples from Brazil, Ceylon, Kenya, Mozambique, Nigeria, and Tanzania have been solvent extracted to recover the phenolic shell liquid (natural CNSL) separate from the kernel oil. The recovered materials from the different sources were present from 23.6% to 27.7%. After hydrogenation of the side chains and methylation of the acidic groups, the component phenols anacardic acid (74.1% to 77.4%), cardol (15.0% to 20.1%), 2‐methyl cardol (1.7% to 2.6%), and cardanol (1.2% to 9.2%) were determined by gas liquid chromatography on polyethyleneglycol adipate. The component phenols have been separated by adsorption thin layer chromatography, and their triene (AN‐15∶3, 36.3% to 50.4%), diene (AN‐15∶2, 17.8% to 32.1%), monoene (AN‐15∶1, 25.0%, to 33.3%), and saturated (AN‐15∶0, 2.2% to 3.0%) constituents determined by mass spectroscopy. The results of mass spectroscopic analysis have been confirmed by methylation of the separated component phenols and gas liquid chromatography. It is apparent that the largest variation is in the % cardanol (1.2% to 9.2%). While the total percentage of unsaturated constituents is quite similar, the distribution of triene, diene, and monoene varies widely.
Effects of ethanol ingestion and dietary fat levels on mitochondrial lipids in male and female rats
Authors: Thompson John A. , Reitz Ronald C.
Published: November 2006

The effects of sex, dietary fat levels, and ethanol ingestion on rat liver mitochondrial lipids have been studied. Two groups of male animals were fed either a low‐fat diet for about 76 days or a high‐fat diet for about 52 days, and two groups of female animals were fed the same low‐fat diet for about 50 days or the high‐fat diet for about 37 days. Ethanol was substituted isocalorically for carbohydrate and amounted to 36% of total calories. The total as well as individual concentrations of fatty acids, phospholipids, and neutral lipids were determined in all eight groups of animals. Variable changes were observed in the total fatty acid composition of mitochondria from each of the four groups of animals. After ethanol ingestion, there was a decrease in arachidonate/linoleate ratio in males, while no change was observed in females. Increasing the fat content of the diet decreased this ratio in both controls and experimentals, but it did not alter the effects of ethanol on either sex. Presumably, this was due to the fact that corn oil was the only source of lipid. After ethanol ingestion, the total fatty acid concentration increased in all groups of animals except the males fed the low‐fat diet. A decrease was observed in this group. The same pattern of change was reflected in changes in total phospholipid concentrations. In each case, the majority of the concentration change in total phospholipid could be accounted for by changes in phosphatidylcholine (PC). Measurement of choline oxidase (C.O.) showed that ethanol ingestion increased C.O. activity only in the low‐fat group of males. No change was observed in the other three groups. Chronic ethanol ingestion is known to increase the methylation of phosphatidylethanolamine (PE); therefore, in order to decrease PC, the increase in C.O. in the low‐fat males must have been of sufficient magnitude to offset the increase in PE methylation. Increasing the fat content of the diet offset the effect of ethanol on C.O. in males. Neither ethanol nor fat exerted much effect on C.O. in females. These results emphasize the importance of dietary levels of fat as well as sex in the study of liver mitochondria structure and function in relation to ethanol metabolism.
Synthesis and mass spectrometry of 1‐acyl and 3‐acyl‐sn‐glycerol carbonates
Authors: Oehlenschläger J. , Gercken G.
Published: November 2006

sn‐Glycerol‐1,2‐carbonate was prepared fromD‐serine,sn‐glycerol‐2,3‐carbonate fromL‐serine, via 1‐0‐ or 3‐0‐benzyl‐sn‐glycerol, respectively.sn‐Glycerol‐2,3‐carbonate was also prepared fromD‐mannitol orD‐serine following thesn‐glycerol‐3‐β,β,β‐trichloroethylcarbonate route.sn‐Glycerol‐1,2‐carbonate andsn‐glycerol‐2,3‐carbonate were acylated with saturated and unsaturated fatty acid chlorides to form 3‐acyl‐sn‐glycerol‐1,2‐carbonates and 1‐acyl‐sn‐glycerol‐2,3‐carbonates, respectively. The mass spectra of the enantiomeric monoacyl‐sn‐glycerol carbonates showed molecular ions and acyl cations (RCO+) of high intensity. The heterocyclic dioxolan‐2‐one ring was remarkably stable during electron impact.
Liver lipid alterations in rats fed arginine deficient diets
Authors: Milner J. A. , Perkins E. G.
Published: November 2006

Arginine deficiency is associated with a marked increase in liver lipids in the rat. Triglyceride accumulation accounts for most of the fatty infiltration. Cholesterol concentration per gram of liver increased approximately 280% above control rats receiving dietary arginine. The percentage of phospholipids was significantly decreased in the arginine‐deficient rat liver compared to controls. The fatty acid composition revealed a significant reduction in the percentage of palmitic, palmitoleic, oleic, and linoleic acids. However, both stearic and arachidonic acids were increased approximately 250 and 160%, respectively, in arginine‐deficient livers compared to controls. Arginine deficiency in the rat causes a marked alteration in lipid metabolism similar to that observed with orotic acid feeding. The similarities of arginine deficiency and orotic acid feeding are discussed.
Long and medium chain triglycerides increase plasma concentrations of ketone bodies in suckling rats
Authors: Yeh Yu‐Yan , Klein Leah Beth , Zee Paulus
Published: November 2006

The potential of medium chain triglyceride (MCT) and long chain triglyceride (LCT) as sources of plasma ketones was investigated in suckling rats. Initially high concentrations of plasma ketones in 6‐, 10‐, and 17‐day‐old rats increased 2‐ to 3‐fold after acute feeding of MCT. This feeding had the same effect in fed or fasted adult rats. Corn oil (as a source of LCT) induced a large increase in the plasma ketone concentration of suckling rats and a relatively small but significant increase in fasted adult rats. The LCT treatment did not affect plasma ketone levels in fed adult rats. The results show clearly that feeding either LCT or MCT will enhance hyperketonemia in suckling rats. In the livers of all animals, regardless of age, the capacity for incorporation of [1‐14C] octanoate into CO2 and acetoacetate far exceeded that for [1‐14C] palmitate. The hyperketonemic action of LCT in suckling rats was accompanied by an increased activity of carnitine palmityltransferase and increased level of carnitine.
Bile acid sulfates: II. Synthesis of 3‐monosulfates of bile acids and their conjugates
Authors: Tserng K. ‐Y. , Klein P. D.
Published: November 2006

Bile acid 3‐monosulfates were synthesized by the sulfation of 3‐hydroxy formyloxy bile acids with sulfur trioxide‐triethylamine in dimethylformamide at 25 C for 0.5 hr. The protecting formyl groups were then hydrolyzed under mild alkaline conditions, and the deformylated products were isolated as p‐toluidinium salts. These p‐toluidinium salts were converted easily to the corresponding disodium salts by methanolic sodium hydroxide. Disodium salts were then isolated by precipitation from methanolether. The corresponding glycine conjugates were similarly synthesized by the sulfation of ethyl esters of 3‐hydroxy formyloxy bile acid glycine conjugates. However, the taurine‐conjugated bile acid sulfates were obtained by conjugating bile acid 3‐monosulfates, either as triethylammonium salt or as disodium salt, with taurine in dimethylformamide in the presence of N‐ethoxycarbonyl‐2‐ethoxy‐1,2‐dihydroquinoline. These procedures produced the desired bile acid sulfates in high yield (typically above 90%) with minimum manipulation. No time‐consuming and capacity‐limited chromatographic purification was needed to isolate the pure sulfates. The thin layer chromatographic mobilities, the infrared spectra, and some of the preliminary studies of the properties of these synthesized 3‐monosulfates are also discussed.
The effects of clofibrate feeding on the metabolism of palmitate and erucate in isolated hepatocytes
Authors: Christiansen Renata Z. , Osmundsen Harald , Borrebaek Borgar , Bremer Jon
Published: November 2006

The metabolism of palmitate and erucate has been investigated in hepatocytes isolated from control rats and from rats fed 0.3% clofibrate. Clofibrate increased the oxidation of [1‐14C]palmitate 1.5 to 2‐fold while the esterification was decreased. At a high concentration of palmitate (1.5 mM), the total rate of fatty acid metabolism was stimulated. Clofibrate stimulated both the oxidation (3.5 to 5‐fold) and the esterification (1.7‐fold) of [14‐14C]erucate. Erucate undergoes chain‐shortening in isolated liver cells. This chain‐shortening was stimulated at least 2‐fold by clofibrate feedings. The isolated mitochondrial fraction from clofibrate‐fed rats showed an increased capacity for oxidation of short‐chain acylcarnitines (including acetylcarnitine), while the oxidation of palmitoyl‐ and erucoylcarnitine showed little change. It is suggested that erucate is shortened by the recently detected β‐oxidation system of peroxisomes.
Fatty acid compositions of lipid fractions from vegetative cells and mature sorocarps of the cellular slime moldDictyostelium discoideum
Authors: Long Byron H. , Coe Elmon L.
Published: November 2006

A wild‐type strain ofDictyostelium discoideum was grown uponAerobacter aerogenes. Fatty acid compositions of lipid fractions and of total lipids obtained from vegetative amoebae and mature sorocarps were compared. Fatty acids isolated from vegetative cells were found to include large quantities of 17‐ and 19‐carbon cyclopropane fatty acids while straight‐chain, saturated fatty acids represented only 10% (w/w) of total fatty acids. These cyclopropane fatty acids appear to be derived from ingested bacteria and are preferentially incorporated into neutral lipids of the slime mold. Development of amoebae to mature sorocarps is accompanied by a substantial decrease in cyclopropane fatty acid content and a concomitant increase in unsaturated fatty acids, mostly as octadeca‐5,11‐dienoic acid. The †‐22 stigmastenyl ester fraction is the richest source of this acid. Fully 65% of the fatty acids in this fraction are the octadecadienoate.
The phospholipids of rabbit type II alveolar epithelial cells: Comparison with lung lavage, lung tissue, alveolar macrophages, and a human alveolar tumor cell line
Authors: Rooney S. A. , Nardone L. L. , Shapiro D. L. , Motoyama E. K. , Gobran L. , Zaehringer N.
Published: November 2006

The phospholipid composition of type II alveolar epithelial cells from the rabbit was compared with that of alveolar macrophages, lung lavage and lung tissue. In addition, the phospholipid composition of a human alveolar tumor cell line, which is morphologically similar to type II cells, was examined. Phosphatidylcholine accounted for 48% of the total phospholipid in the type II cells, 41% in the tumor cells, and 30% in the macrophages. Phosphatidylcholine was 51% disaturated in the type II cells, 54% in lung lavage, 39% in whole lung, 29% in lavaged lung and macrophages, and 16% in the tumor cells. Palmitic acid was the major fatty acid in phosphatidylcholine from all samples with the exception of the tumor cells in which almost half of the fatty acids were accounted for by oleic acid. The phospholipids of the type II cells were more similar to those of lung lavage, and thus surfactant, than to lung tissue and macrophages. This is consistent with their supposed role in surfactant production. The tumor cells, although morphologically similar to type II cells, were quite different with respect to phospholipid composition.
Hepatic triglyceride lipase deficiency in liver disease
Authors: Freeman Michael , Kuiken Lois , Ragland James B. , Sabesin Seymour M.
Published: November 2006

The activity of post‐heparin lipases in patients with alcoholic hepatitis and viral hepatitis was evaluated. Lipoprotein lipase and hepatic triglyceride lipase were differentiated by assay under high and low salt conditions and also by separation on heparin‐agarose affinity chromatography columns. The mean activity of hepatic triglyceride lipase in the sera of liver disease patients was only 21–24% of the mean of controls, but lipoprotein lipase in patients' sera was not different from normal levels. Hepatic triglyceride lipase deficiency may partially account for the accumulation of a triglyceride‐rich low density lipoprotein in liver disease.
Stimulation of hepatic lipogenesis by eicosa‐5,8,11,14‐tetraynoic acid in mice fed a high linoleate diet
Authors: Abraham S. , McGrath Hope , Ananda Rao G.
Published: November 2006

Liver slices, from mice fasted for one day and then refed for three days either a 15% corn oil diet or a 15% corn oil diet containing eicosa‐5,8,11,14‐tetraynoic acid (TYA), were incubated with [1‐14C] acetate or [3H]H2O to determine lipogenic capacity. Dietary TYA produced a twofold stimulation in fatty acid and cholesterol synthesis. TYA also caused an increase in the relative proportion of linoleate (C18∶2) and a decrease in that of arachidonate (C20∶4) in liver. Thus, (a) despite high levels of C18∶2, hepatic lipogenesis can be increased, and (b) even short term feeding of TYA can alter the hepatic fatty acid composition presumably by inhibition of arachidonate synthesis from linoleate.
Phosphono‐lipid content of the oyster,Crassostrea virginica, in three physiological conditions
Authors: Swift Mary L.
Published: November 2006

The distribution of lipid‐bound phosphorus between the phosphodiester and phosphonate forms was determined for the oyster in three physiological conditions. The adductor muscle had the highest level of phosphonate phosphorus, 92 μg/g wet weight tissue, or 40.4% of all muscle phospholipids. The total phospholipid level (μg/g wet weight tissue) increased in all tissues of the oyster during starvation, as did the percentage of phosphonolipids in all tissues except the adductor muscle, in which it remained constant. These data suggest that during starvation the phosphonate bonds are conserved at the expense of phosphodiester bonds in oyster lipids.
Bis‐phosphatidic acid in developing soybeans and soybean suspension cultures
Authors: Stearns E. M. , Morton W. T.
Published: November 2006

A phospholipid which rapidly accumulates radioactivity from [1‐14C] acetate administered to slices of developing soybeans or to suspension cultures of soybean cells was isolated. Its structure was identified by comparison of its properties and degradation products with those of authentic lipid standards using infrared absorption spectrometry, thin layer chromatography, acetolysis, mild alkaline hydrolysis, and determination of molar ratios of phosphorus, glycerol, and acyl moieties. The structure of the phospholipid was found to bebis‐phosphatidic acid, a phospholipid previously unreported in higher plants.
Metabolism and tissue distribution of label from [9,10‐methylene‐14C] sterculic acid in the rat
Authors: Nixon J. E. , Yoss J. K. , Eisele T. A. , Pawlowski N. E. , Sinnhuber R. O.
Published: November 2006

The metabolism of14C‐sterculic acid, labeled in the methylene carbon of the cyclopropene ring, was investigated in Wistar rats. Comparison of the distribution of radioactivity in tissue and excreta as a function of time showed that the free sterculic acid was metabolized faster than the methyl ester and that the sterculic acid administered by intragastric intubation was absorbed and metabolized at a faster rate than that administered by intraperitoneal injection. The concentration of label in blood serum reached a maximum 2 hr after intubation and then rapidly declined. Incorporation of radioactivity into most organs peaked at 4 hr with liver peaking at a maximum of 11% of the administered dose and other organs at less than 1%. Label in depot fat steadily increased to 8% at 26 hr. Less than 1% of the administered dose was expired in CO2 in the same time period. Excretion of label reached a maximum of 48% in urine and 11% in feces by 16 hr. The majority of the label in liver was in the fatty acid portion of the lipid fraction. The relative amount of label in microsomal and mitochondrial subcellular fractions of liver changed with time suggesting that these organelles may be involved in the metabolism of sterculic acid. Rats fed control diets appeared to metabolize sterculic acid in the same manner, but at a slower rate than rats acclimated to dietary cyclopropene fatty acids. Low recovery of label in expired air showed that the methylene carbon of the cyclopropene ring was not oxidized to CO2. These data suggest that rats readily absorb sterculic acid and excrete labeled compounds primarily in the urine.
Role and mechanism of peripheral fatty acid mobilization in 2‐mercaptoethanol‐induced fatty liver
Authors: Sabourault D. , Giudicelli Y. , Nordmann J. , Nordmann R.
Published: November 2006

2‐Mercaptoethanol‐induced fatty liver involves an increased free fatty acid mobilization which is primarily due to an inhibition of free fatty acid reesterification in adipose tissue. Furthermore, increased free fatty acid mobilization as well as fatty liver induction are not induced by 2‐mercaptoethanol per se but result most probably from 2‐mercaptoacetate through oxidation of 2‐mercaptoethanol.
Cysteine adds to lipid hydroperoxide
Authors: Gardner H. W. , Kleiman R. , Weisleder D. , Inglett G. E.
Published: November 2006

Cysteine reacts with linoleic acid hydroperoxide to yield several products, some of which were identified as fatty acid‐cysteine adducts. The addition was catalyzed by ferric chloride (10−5 M) by initiating free radical reactions. When isomerically pure 13‐hydroperoxy‐cis‐9,trans‐11‐octadecadienoic acid and cysteine were reacted in 80% ethanol under N2, the major adducts were 9‐S‐cysteine‐13‐hydroxy‐10‐ethoxy‐trans‐11‐octadecenoic acid (I) and 9‐S‐cysteine‐10,13‐dihydroxy‐trans‐11‐octadecenoic acid (II). When the reaction included both isomers of the hydroperoxide (13‐and 9‐hydroperoxide) and air, an adduct of 9‐oxononanoic acid and cysteine also was isolated. Additional experiments gave information about possible mechanisms of I and II formation.
Accumulation of ergosta‐8,14‐dien‐3β‐ol bySaccharomyces cerevisiae cultured with an azasterol antimycotic agent
Authors: Hays P. R. , Parks L. W. , Pierce H. D. , Oehlschlager A. C.
Published: November 2006

15‐Aza‐24‐methylene‐D‐homocholesta‐8,14‐dien‐3β‐ol, an antimycotic agent, at a concentration of 75 ng/ml inhibited ergosterol biosynthesis inSaccharomyces cerevisiae strain 3701 B resulting in the accumulation of an unusual sterol. Experimental data presented indicate that this sterol is ergosta‐8,14‐dien‐3β‐ol. The accumulation of the compound is supportive of current models of biosynthetic pathways for sterols in yeast and is consistent with inhibition by the azasterol of the Δ14 sterol reductase.
Effects of a single ingestion of sodium taurocholate on esterified cholesterol concentration in liver and cholesterol turnover in the rat
Authors: Mathé D. , Chevallier F.
Published: November 2006

The overall response of the rat's cholesterol metabolism to a single ingestion of taurocholate (80 mg) was studied with the isotopic equilibrium method. The bile acid production, measured by the daily14CO2 output of rats in isotopic equilibrium of [26‐14C]‐cholesterol, initially decreased and then increased. Conversely, the hepatic concentration of esterified cholesterol first increased and then decreased. Moreover, the ingestion of taurocholate increasing the intestinal absorption coefficient of dietary cholesterol increased the abosprtion and decreased the fecal excretion and the intestinal biosynthesis of cholesterol. The balance of these last effects is an excess cholesterol inflow. The classical hypothesis of negative feedback regulation of bile acid production fails to explain the observed biphasic effect of taurocholate. This compound, when its origin is exogenous, appears to stimulate the storage of esterified cholesterol in the liver, at the expense of bile acid synthesis. This accumulation rate takes into account not only the decrease in cholesterol transformation into bile acids but also the excess inflow of cholesterol. As the exogenous taurocholate was eliminated from the body, cholesteryl ester hydrolysis occurred and provided a supplementary source of free cholesterol for bile acid synthesis.
Effect of tibric acid on hepatic cholesterol synthesis in rats
Authors: Cayen M. N. , Dubuc J. , Dvornik D.
Published: November 2006

Male albino rats were administered various oral doses of tibric acid daily for 1 week. Serum cholesterol and triglyceride levels were reduced, but total liver content of cholesterol, phospholipids, and triglycerides was increased. Tibric acid treatment suppressed the incorporation of both [14C] acetate and [3H] mevalonate into cholesterol by liver homogenates.
Fatty acids in femaleMacracanthorhynchus hirudinaceus (Acanthocephala)
Authors: Smith Wayne , Dunagan T. T. , Miller Donald M.
Published: November 2006

Neutral lipids and phospholipids in the body wall, lemnisci and pseudocoel and neutral lipids of fluid found in the “tube” system of the lemnisci and the lacunar system of the body wall ofMacracanthorhynchus hirudinaceus (Acanthocephala) were determined by the technique of thin layer chromtography and gas chromatography (GC). Sixteen different fatty acids from nonpolar lipids were identified as follows: 8∶0, 10∶0, 11∶0, 12∶0, 13∶0, 14∶0, 14∶1, 16∶0, 18∶0, 18∶1, 18∶2 and/or 20∶0, 18∶3 and/or 20∶1, 20∶3, 22∶1, 24∶1 and 22∶6. In addition, there were three unidentified GC peaks corresponding to chain lengths greater than 20 carbons. Sixteen different fatty acids from phospholipids were identified in each of the three fractions analyzed. They were as follows: 10∶0, 11∶0, 12∶0, 13∶0, 14∶0, 14∶1, 16∶0, 16∶1, 18∶0, 18∶1, 18∶2 and/or 20∶0, 20∶2, 20∶3, 22∶1, 24∶1, and 22∶6. Four unidentified peaks were also observed. There was a significant difference in the percentage of lipid as well as the concentration of particular fatty acids when each fraction was compared. There was also an abundant supply of sterols and glycerides in each fraction.
In vitro conversion of erucic acid by microsomes and mitochondria from liver, kidneys and heart of rats
Authors: Clouet Pierre , Bezard Jean
Published: November 2006

Microsomes and mitochondria of liver, kidneys, and heart were incubated with [14‐14C]erucic acid in three assay media: one favorable for chain elongation (NADPH+KCN), another favorable for β‐oxidation and the last one for shortening (NADP+KCN). Elongating reactions occurred mainly in microsomes, those of kidneys being very active; the mitochondria also showed some activity, heart mitochondria being, however, more active than the microsomes, when considering the amount of erucic acid activated. In the medium for β‐oxidation, practically no shortened fatty acids were found. On the contrary, when β‐oxidation was inhibited, and in the presence of NADP, the formation of shorter monoenes, probably in the outer membrane of the mitochondria, was observed, namely eicosenoic acid in high amount, oleic acid and hexadecenoic acid. Mitochondria from liver were very active as were those of heart, when compared with the quantity of activated erucic acid. In heart, the mitochondria shortened erucic acid into oleic acid and hexadecenoic acid, which were then probably used as energy substrates. With carnitine and without NADP, shortened fatty acids were formed in the mitochondria of liver, probably by the first reactions of β‐oxidation. In this case, the proportions of oleic acid and hexadecenoic acid were higher than with NADP alone. In the presence of carnitine and NADP, the level of the chain‐shortening reaction did not differ from that observed with NADP alone. It appears, therefore, that the activated erucic acid is mainly directed towards shortening reactions and not towards transfer reactions across the mitochondrial membranes.
The effects of phenobarbital on biliary lipid metabolism in cholesterol gallstone subjects
Authors: Redinger R. N.
Published: November 2006

The effect of 1.7–2.2 mg/day oral phenobarbital over short (1 MO) and long term (6–24 MO) treatment on primary bile acid (BA) secretion, composition, synthesis, pool size, and enterohepatic cycling rates as well as phospholipid (PL) and cholesterol (C) secretion rates and biliary composition was determined in 12 asymptomatic cholesterol gallstone subjects while 5 normals had only short term studies. Phenobarbital enhanced BA and C secretion (BA‐636±166 to 2110±382 mg/hr, p<0.001 and C‐42±5 to 224±48 mg/hr, p<0.001) and BA cycling rate in all subjects studied during stimulated enterohepatic circulation but, during fasting, it only enhanced BA secretion (451±129 vs. 759±159 mg/hr, p<0.05) in gallstone subjects. Cholic acid (CA) production rate (171±28 to 395±9 mg/hr, p<0.05) and pool size (727±80 to 1209±132 mg/hr, p<0.05) were increased during long term treatment of gallstone subjects, while the proportion of CA in bile and deoxycholic acid (DCA) in feces increased. Treatment decreased biliary cholesterol from supersaturated to saturated levels (9.5±0.6 vs. 6.1±0.9 moles%, p<0.02) in all fasting gallstone subjects and decreased cholesterol crystal loads during long term treatment; but, while prohibiting gallstone growth, it did not affect stone dissolution over 24 month's treatment. Phenobarbital also failed to affect biliary lipid composition or bile acid pool size in short term treatment of normals. Thus, phenobarbital affected hepatic metabolism of CA by enhancing production rate, secretion, and pool size; and in testinal metabolism of both CA and chenodeoxycholic (CDC) acids by increasing their cycling rates. Phenobarbital may have failed to produce stone dissolution by enhancing CA production and pool size more than that of CDC.
The content and composition of sterols and sterol esters in sunflower and poppy seed oils
Authors: Johansson Anna
Published: November 2006

The composition and proportion of free sterols and sterol esters in crude sunflower and poppy seed oils were determined, using preparative thin layer chromatography followed by gas chromatography with cholesterol as an internal standard. Free sterols and sterol esters were also isolated in a liquid fraction obtained by low temperature crystallization (−80 C) of the oils and enriched with minor lipid classes. This enrichment procedure provided a liquid fraction suitable for studies of minor components in the oils. However, selectivity towards sterol esters was observed since sterols esterified to very long chain fatty acids (C20–C24) were preferentially retained in the precipitate. The proportions of free and esterified sterols were found to be 0.34 and 0.28%, respectively, in the sunflower oil, whereas the corresponding figures for poppy seed oil were 0.33% and 0.05%. Sunflower oil was characterized by a relatively high percentage of Δ7‐sterols, preferentially obtained in the esterified fraction, and by very long chain saturated fatty acids of sterol esters. The sterols in poppy seed oil were composed almost entirely of campesterol, stigmasterol, sitosterol and Δ5‐avenasterol, although their percentage distributions were remarkably different in the free and esterified fraction.
Distribution of hexadecenoic, octadecenoic and octadecadienoic acid isomers in human tissue lipids
Authors: Adlof R. O. , Emken E. A.
Published: November 2006

Thetrans 16∶1, 18∶1 and 18∶2 fatty acid composition of various human organ lipids was studied to determine if isomers accumulated in specific tissues. “Trans” isomers are defined as those fatty acids containing one or moretrans double bonds. Adipose, kidney, brain, heart and liver tissue lipids were analyzed. Gas chromatography with a 100‐SP2560 capillary column was used to characterize the various positional and/or geometrical isomers. The distribution ofrans 16∶1 and 18∶1 isomers ranged from 0.3% in the brain to 4.0% in adipose tissue, whiletrans 18∶2 isomers ranged from 0.0% in the brain to 0.4% in adipose tissue. Notrans 18∶3 isomers were detected. Positional isomer ratios forcis 16∶1 (Δ9 vs Δ7) andcis 18∶1 (Δ11 vs Δ9) were also determined. Since these ratios are reproducible from one individual to the next, they might be useful for diagnosis of human metabolic disorders.
Prostaglandin‐like substances formed during autoxidation of methyl linolenate
Authors: Nakamura Takashi
Published: November 2006

Prostaglandin‐like substances other than 3‐(2‐ethyl‐5‐hydroxy‐3‐oxo)‐cyclopentanyl‐2‐propenal (compound I), which upon reacting with amino acids form reddish pigments, were purified, and their chemical structures were determined. Three red pigment‐forming substances (RPS) in autoxidized methyl linolenate were purified successively by gel chromatography on Sephadex LH‐20, column chromatography and thin layer chromatography on Silica Gel 60, and by high performance liquid chromatography on μ‐Porasil. IR spectra of the RPS showed the absorption of an ester group (νC=O 1730 cm−1 in CHCl3) and of a longer branched chain (νC‐H 2800–3100 cm−1), in addition to the absorption bands observed in compound I. Electron impact mass spectra of the trimethylsilyl ethers obtained after reduction with NaBH4 and NaBD4 were analyzed in detail and compared with those of compound I. The structures of the RPS were identified as stereoisomeric methyl 8‐[2‐(2‐formylvinyl)‐3‐hydroxy‐5‐oxo‐cyclopentanyl]‐octanoates derived from methyl 12‐hydroperoxy‐linolenate.
Rat hepatocyte plasma membrane acyl:CoA synthetase activity
Authors: Davidson B. C. , Cantrill R. C.
Published: November 2006

The presence of long chain acyl:CoA synthetases in mammalian microsomes and mitochondria has been established previously by Aas (Biochim. Biophys. Acta 231, 32–47 [1971]). The presence of a plasma membrane‐associated enzyme was investigated in rat hepatocyte plasma membranes, where an enzyme exhibiting high activity and with a preferred substrate of 18‐carbon chain length was discovered. The results are consistent with the presence of a single enzyme. The effect of the degree of unsaturation of the fatty acid substrates was not as pronounced as that arising from the length of the carbon chain. The pattern of substrate preference of the enzyme was ω3 polyenoic fatty acids >ω6 polyenoic acids >ω9 monoenoic acids > saturated acids. This may relate to the similar substrate preference pattern exhibited by the fatty acyl desaturase enzymes. The role played by long chain acyl:CoA synthetase in hepatocyte metabolism is uncertain, but it may relate to the incorporation of polyenoic fatty acids from the circulation into cell membranes and the trapping of other fatty acids within the cell for further metabolism.
A hydrophilic bile acid effects partial dissolution of cholesterol gallstones in the prairie dog
Authors: Cohen Bertram I. , Mosbach Erwin H. , McSherry Charles K. , Rzigalinski Beverly , Kuroki Syoji
Published: November 2006

Gallstone formation and dissolution were studied in a prairie dog model of cholesterol (CH) cholelithiasis. Gallstones were induced in 49 prairie dogs by feeding 1.2% CH in a nutritionally adequate semisynthetic diet for 6 wk (period 1). At 6 wk, gallstones had developed in all animals examined. The diets were modified by reducing the amounts of CH to 0.4, 0.2, 0.1 and 0.0% (diets 1–4); hyodeoxycholic acid (HDA; 30 mg/kg/day) was added to these diets (diets 5–8). All animals were fed the modified experimental diets for an additional 8 wk (period 2). At week 14, spontaneous gallstone dissolution had not occurred, even in the groups given no added dietary CH during period 2 (group 4). Addition of HDA to the diet tended to reduce the incidence of biliary CH crystals and the size and number of CH gallstones. Biliary CH remained elevated and the lithogenic indices in all groups were found to be greater than 1.0 at the end of the experiment. Liver and plasma CH levels tended to be lower in the groups fed HDA. In these groups, HDA and 6βHDA became the major biliary bile acids. This study demonstrates that HDA achieved partial dissolution of gallstones in bile supersaturated with CH.
Inhibition of the antidiuretic hormone hydroosmotic response by phospholipids and phospholipid metabolites
Authors: Tarapoom Nimman , Royce Ron , Yorio Thomas
Published: November 2006

Phospholipid metabolities and phospholipids containing arachidonic acid (AA) inhibited the antidiuretic hormone (ADH)‐induced increase in transepithelial water flow in the toad urinary bladder, but had no effect on basal water flow when added to the serosal bathing solution. Other fatty acid‐substituted phospholipid metabolites had no effect on osmotic water movement in the presence or absence of ADH. Indomethacin attenuated the inhibitory effects of the AA containing phospholipid metabolities (PMAA), suggesting that the PMAA response required AA release and prostaglandin (PG) formation. PMAA increased PGE formation as measured by radioimmunoassay. PG have been reported to inhibit ADH‐stimulated water flow by inhibiting adenylcyclase. PGE2 (10−8 M) had no effect on cyclic AMP‐stimulated water flow, whereas exogenous AA and PMAA attenuated the hydroosmotic response to added cyclic AMP. Indomethacin only partially reversed the inhibition by AA of the cyclic AMP‐associated water movement, suggesting that the inhibition by AA and PMAA may involve other metabolites of AA than PG.

PG and the AA cascade have been implicated as cellular modulators of the ADH hydroosmotic response. The present results offer additional support to the theory that this system may regulate the intracellular events that are transduced following receptor activation by ADH.
Lack of regioselectivity in formation of oxohydroxyoctadecenoic acids from the 9‐ or 13‐hydroperoxide of linoleic acid
Authors: Gardner H. W. , Kleiman R.
Published: November 2006

Either 9‐hydroperoxy‐trans‐10,cis‐12‐octadecadienoic acid or 13‐hydroperoxy‐cis‐9,trans‐11‐octadecadienoic acid was treated with the catalyst, cysteine‐FeCl3, in the presence of oxygen. Oxohydroxyoctadecenoic acids were among the many products formed as a result of hydroperoxide decomposition. A mixture of 9(13)‐oxo‐13(9)‐hydroxy‐trans‐11(10)‐octadecenoic acids (δ‐ketols) was produced from either isomeric hydroperoxide. The formation of isomeric δ‐ketols from 9‐hydroxy‐trans‐12,13‐epoxy‐trans‐10‐octadecenoic acid (epoxyol), a known product of 13‐hydroperoxy‐cis‐9,trans‐11‐octadecadienoic acid decomposition, implies that the epoxyol is an intermediate. The mechanism was elucidated by the facile conversion of the epoxyol (methyl ester_ to methyl 9(13)‐oxo‐13(9)‐hydroxy‐trans‐11(10)‐octadecenoates with a Lewis acid, BF3‐etherate.
A simplified procedure for the determination of betaine in liver
Authors: Barak A. J. , Tuma D. J.
Published: November 2006

A convenient procedure for the determination of hepatic betaine levels is described. The method takes advantage of ethanol precipitation to rid acidified tissue extracts of interfering substances. Betaine is reacted with potassium triiodide to form betaine periodide, which is selectively precipitated via pH adjustment. The precipitate of betaine periodide is dissolved in ethylene dichloride and measured spectrophotometrically. The method is specific, accurate, and simple and showed recoveries of from 97 to 103% at two different levels of added betaine. The applicability of the method was shown when it was demonstrated that diets containing different amounts of choline influenced levels of hepatic betaine.
pH gradient electrophoresis and isoelectric focusing of lipoproteins on agarose bead thin layers
Authors: Vost A. , Pocock D. M. ‐E. , Pleet S.
Published: November 2006

A new method of isoelectric focusing (IEF) and pH gradient electrophoresis, using thin layers of agarose gel beads, was devised to investigate chylomicrons and very low density lipoproteins (VLDL). pH gradient stability and cathodal gradient drift were similar to those of polyacrylamide gel IEF, and linearity of gradients was maintained for 23 hr. Chylomicrons and VLDL were detectable without staining. Chylomicrons from human serum and from rat lymph migrated in this system. Rat lymph chylomicrons, obtained by ultracentrifugation, migrated in several discrete bands, and this heterogeneity of rat chylomicrons was confirmed by electron microscopic demonstration of chylomicrons in each band. This new technique has permitted the first measurement of isoelectric points of some lipoproteins in the ultracentrifuged fraction of human serum chylomicrons and the first separation of multiple discrete fractions of ultracentrifuged lymph chylomicrons.
Identification of ergosta‐8,24(28)‐dien‐3β,6α‐diol in A Δ8 → Δ7 sterol isomerase‐blocked yeast mutantsterol isomerase‐blocked yeast mutant
Authors: Pierce A. M. , Pierce H. D. , Unrau A. M. , Oehlschlager A. C. , Woods R. A.
Published: November 2006

In addition to the monohydroxysterols found in the Δ8 → Δ7 isomerase‐blockedSaccharomyces cerevisiae mutanterg 2, a novel dihydroxysterol, ergosta‐8,24(28)‐dien‐3β,6α‐diol, was isolated. This sterol accumulated to the extent of 2.1% of the total sterol fraction when this mutant was treated with 23‐azacholesterol, a known inhibitor of the 24‐methylene‐sterol‐24(28)‐reductase.
Inhibition of hepatic lipogenesis by 2‐tetradecylglycidic acid
Authors: McCune Sylvia A. , Nomura Takahide , Harris Robert A.
Published: November 2006

2‐Tetradecylglycidic acid (TDGA), a hypoglycemic agent, has been found to be a very effective inhibitor of de novo fatty acid synthesis by isolated hepatocytes. A comparison was made between the effectiveness of TDGA and 5‐(tetradecyloxy)‐2‐furoic acid (TOFA), a hypolipidemic agent, on the metabolic processes of isolated hepatocytes. These compounds are structurally related and both inhibit fatty acid synthesis; however, they have opposite effects from each other on the oxidation and esterification of fatty acids. TDGA inhibits whereas TOFA stimulates fatty acid oxidation. TDGA stimulates whereas TOFA inhibits fatty acid esterification.