bluuebunny/crossref_metadata_2025_split huggingface dataset:
Iron‐catalyzed reaction products of α‐tocopherol with methyl 13(S)‐hydroperoxy‐9(Z),11(E)‐octadecadienoate
Authors: Yamauchi Ryo , Yamamoto Norio , Kato Koji 
Published: November 2006

Abstractα‐Tocopherol was reacted with methyl 13(S)‐hydroperoxy‐9(Z),11(E)‐octadecadienoate in the presence of an iron‐chelate, Fe(III)‐acetylacetonate, at 37°C in benzene. The reaction was carried out either aerobically or anaerobically. The main products of α‐tocopherol under air were isolated and identified as two stereoisomers of 4a,5‐epoxy‐8a‐hydroperoxy‐α‐tocopherone, four stereoisomers of methyl 9‐(8a‐dioxy‐α‐tocopherone)‐12,13‐epoxy‐10(E)‐octadecenoate, four stereoisomers of methyl 11‐(8a‐dioxy‐α‐tocopherone)‐12,13‐epoxy‐9(Z)‐octadecenoate, two stereoisomers of methyl 13(S)‐(8a‐dioxy‐α‐tocopherone)‐9(Z),11(E)‐octadecadinoate, and α‐tocopherol dimer. Besides the 8a‐(lipid‐peroxy)‐α‐tocopherones, two stereoisomers of methyl 11‐(α‐tocopheroxy)‐12(S),13(S)‐epoxy‐9(E)‐octadecenoate, two stereoisomers of methyl 9‐(α‐tocopheroxy)‐12(S),13(S)‐epoxy‐10(E)‐octadecenoate, and two isomers of methyl (α‐tocopheroxy)‐octadecadienoate were obtained under nitrogen atmosphere. The results indicate that the peroxyl radicals from lipid hydroperoxides prefer to react with the 8a‐carbon radical of α‐tocopherol and the carbon‐centered radicals react with the phenoxyl radical of α‐tocopherol.
Dietary fats rich in saturated fatty acids (12∶0, 14∶0, and 16∶0) enhance gallstone formation relative to monounsaturated fat (18∶1) in cholesterol‐fed hamsters
Authors: Jonnalagadda Satya S. , Trautwein Elke A. , Hayes K. C. 
Published: November 2006

AbstractTo test the possibility that dietary palmitic acid (16∶0) may be lithogenic, different fats were blended to exchange 18∶1 in olive oil with either 16∶0 in palm stearin, 12∶0+14∶0 in coconut oil, or 14∶0+16∶0 in butterfat. Dietary 18∶2 was held constant at 1.2% energy (en) (with extra safflower oil as needed) in these four purified diets containing low fat (11% of total energy) and 0.4% cholesterol. A fifth, high‐fat diet provided 40% of the total energy as the 16∶0‐rich blend. All hamsters fed the low‐fat, 16∶0‐rich blend for six weeks developed cholesterol gallstones (8/8). Although the gallstone incidence was lower for the 12∶0+14∶0‐rich diet (5/8), the severity of stone formation in affected hamsters was equal to that in the low‐fat, 16∶0‐rich group. Mucin accumulation in gallbladder bile was often associated with cholesterol gallstones in diets containing 16∶0, but was minimal in 18∶1‐rich and 12∶0+14∶0‐rich groups. Neither the lithogenic index (all>1.0), plasma lipids, nor liver cholesterol was a selective predictor of stone formation. The high‐fat, 16∶0‐rich diet actually decreased cholesterol stone incidence (3/8) and severity, but yielded a high incidence of pigment stones (5/8). Thus, saturated fat and 16∶0per se were not responsible for the exaggerated lithogenesis. Because the antilithogenic 18∶1‐rich diet also normalized the 18∶2 intake (1.2% en) relative to previous butter diets (0.3% en), the potential importance of essential fatty acids (EFA) deficiency in the model was tested in a second study by feeding graded amounts of 18∶2 (0.3, 0.6, 0.9, and 1.2% en) as safflower oil in four low‐fat, butter‐rich diets (11% en as fat) without alleviating gallstone incidence or severity. These studies indicate that substitution of 18∶1 for saturated fatty acids in low‐fat diets reduces gallstone formation without affecting the lithogenic index. Furthermore, intake of 18∶2 at or below the EFA requirement does not appear to be a major factor in this model.
Reduction of hyperlipidemia in hepatoma‐bearing rats by dietary fish oil
Authors: Kawasaki Masashi , Yagasaki Kazumi , Miura Yutaka , Funabiki Ryuhei 
Published: November 2006

AbstractThe effect of dietary fish oil on serum lipid levels was studied by comparing it with dietary corn oil in Donryu rats subcutaneously implanted with an ascites hepatoma cell line (AH109A). The hepatoma‐bearing rats exhibited hyperlipidemia charactarized by a rise in both serum cholesterol and triglyceride levels. Increased cholesterogenesis in the host liver and decrease steroid excretion into feces are suggested to be responsible for the hepatoma‐induced hypercholesterolemia, and increased fatty acid mobilization from peripheral adipose tissues and decreased triglyceride clearance from the blood circulation are considered causes for the hepatoma‐induced hypertriglyceridemia. Dietary fish oil reduced the hyperfipidemia in these animals, suppressed the hepatoma‐induced increase in hepatic cholesterogenesis and fatty acid mobilization from adipose tissue. Dietary fish oil also tended to increase fatty acid oxidation in the liver. Such diverse effects of fish oil may lead to the reduction of the hepatoma‐induced hyperlipidemia. These results suggest that studies on dietary fish oil may be warranted in patients with cancer‐related hyperlipidemia.
Dietary deficiency of docosahexaenoic acid impairs vision at low light intensities in juvenile herring (Clupea harengus L.)
Authors: Bell Michael V. , Batty Robert S. , Dick James R. , Fretwell Karen , Navarro Juan Carlos , Sargent John R. 
Published: November 2006

AbstractIn the retina of herring (Clupea harengus L.), rods are recruited from about 8 wk after hatching, and from this time there is a linear relationship between the number of rods in the photoreceptor cell population and the content of di22∶6n−3 molecular species of phospholipids. Juvenile herring were reared from four weeks' post‐hatching for 15 wk on eitherArtemia nauplii deficient in 22∶6n−3 or on enrichedArtemia nauplii containing 4.3% 22∶6n−3. The visual performance of the fish was then determined at three light intensities (0.01, 0.1, and 1.0 lux) by observing their frequency of striking at liveArtemia nauplii using infrared video recording. Herring reared on the diet containing no 22∶6n−3 were less active predators, especially at the lowest light intensity where very few strikes were observed. The eyes of these fish contained greatly reduced levels of di22∶6n−3 molecular species of total phospholipid, 2.1% vs. 12.0% in fish supplemented with 22∶6n−3. The contribution of saturated and monounsaturated fatty acids in the molecular species of phosphatidylethanolamine (PE), phosphatidylserine (PS), and phosphatidylcholine (PC) was virtually unchanged, while 20∶5n−3 and 22∶5n−3 largely replaced 22∶6n−3. There was an almost complete disappearance of di22∶6n−3 PC, while the amounts of di22∶6n−3 PE and PS fell by 18.1 and 20.6% to 2.7 and 7.6%, respectively. The dipolyunsaturated molecular species di20∶5n−3, 20∶5n−3/22∶5n−3, and di22∶5n−3 made up a substantial part of the deficit. We conclude that a dietary deficiency of 22∶6n−3 during the period early in rod development impairs visual performance such that the fish can no longer feed at low light intensities.
Eicosanoid generating capacities of different tissues from the rainbow trout,Oncorhynchus mykiss
Authors: Knight John , Holland Jason W. , Bowden Linda A. , Halliday Katrina , Rowley Andrew F. 
Published: November 2006

AbstractThe eicosanoid generating potential of the brain, gills, skin, ovary, muscle, eye, liver, spleen, heart, and alimentary canal in the rainbow trout,Oncorhynchus mykiss, was examined. All the organs/tissues examined synthesized the 12‐lipoxygenase products, 12‐hydroxyeicosatetraenoic acid (12‐HETE), and 12‐hydroxyeicosapentaenoic acid (12‐HEPE), implying the widespread nature of this enzyme in trout. Both prostaglandin E and LTC were also found in variable amounts in the organs, with the greatest amount of PGE found in the gill. Leukotriene (LT) B4 and LTB5 were found in supernatants from calcium ionophore‐challenged brain, skin, ovary, liver, spleen, and heart, but the lipoxins A4 and A5 were only present in brain, ovary, and spleen in relatively small amounts. As lipoxins have previously been shown to be synthesized by macrophages in rainbow trout [Pettittet al., J. Biol. Chem. 266, 8720–8726 (1991)], and related cells (microglial cells) are found in the brain of mammals, the localization of macrophage‐like cells in trout brain was investigated immunocytochemically. Monoclonal antibodies specific for trout leucocytes failed to identifity any microglial‐like cells in sections of the brain, although microvessels containing immuno‐positive reaction products were observed. A number of distinct lipoxygenase products were found in supernatants of ionophore‐challenged gill, including 14‐hydroxydocosahexaenoic acid, 12‐HETE, and 12‐HEPE, and a large number of dihydroxy fatty acid derivatives with conjugated triene chromophores. One of these products was tentatively identified as 8(R),15(S)‐dihydroxyeicosatetraenoic acid, a dual 12‐ and 15‐lipoxygenase product, but apparently no LTB4 was generated by this tissue.
New branched‐chain fatty acids from the senegalese gorgonianLeptogorgia piccola (white and yellow morphs)
Authors: Mirallès Joseph , Barnathan Gilles , Galonnier Renée , Sall Thioro , Samb Abdoulaye , Gaydou Emile Marcel , Kornprobst Jean‐Michel 
Published: November 2006

AbstractFatty acids from total lipids of the gorgonianLeptogorgia piccola (white and yellow morphs), collected from the same area at two different periods with regard to the average water temperature, were studied. More than fifty fatty acids were identified as methyl esters andN‐acyl pyrrolidides by gas chromatography and gas chromatography/mass spectrometry. Three new, branched‐chain unsaturated fatty acids were identified in addition to the unusual 7‐methyl‐6‐hexadecenoic acid, namely 10‐methyl‐6‐hexadecenoic, 7,9‐dimethyl‐6‐hexadecenoic, and 10‐methyl‐6,9‐heptadecadienoic acids. Also 6,9‐heptadecadienoic acid was identified. The fatty acid patterns of specimens harvested in colder waters were quite different from those harvested in warmer waters in that the former contained high amounts of methylene‐interrupted polyunsaturated acids, including tetracosapolyenoic acids, especially 6,9,12,15,18–24∶5 (up to 15.8% of the total acid mixture) and 6,9,12,15,18,21–24∶6 (up to 5.3%). Arachidonic acid was, nevertheless, a major component in all the fatty acid mixtures studied (13.6–20.5%). Based on gas chromatography/Fourier transform infrared experiments, the double bonds were assigned the (Z) configuration. Several fatty aldehydes and their dimethyl acetals were also detected, of which the most abundant was octadecanal.
Dietary manipulation of long‐chain polyunsaturated fatty acids in the retina and brain of guinea pigs
Authors: Weisinger Harrison S. , Vingrys Algis J. , Sinclair Andrew J. 
Published: November 2006

AbstractHigh levels of n−6 docosapentaenoic acid (22∶5n−6) have been reported in the retina of guinea pigs fed commercially‐prepared grain‐based rations (commercial diet). In rats and monkeys, high levels of 22∶5n−6 are an indicator of n−3 polyunsaturated fatty acid (PUFA) deficiency. We have examined the fatty acid composition of the retina and brain in guinea pigs fed a commercial diet or one of three semi‐purified diets containing three different levels of n−3 PUFA. The diets comprised a diet deficient in n−3 PUFA (semi‐purified diet containing safflower oil), two diets containing α‐linolenic acid (standard commercial laboratory diet and semi‐purified diet containing canola oil), and a diet containing α‐linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid (DHA) (semi‐purified diet containing canola oil, safflower oil, and fish oil). Two groups of guinea pigs were given the diets from day 1 to 4 wk or day 1 to 8 wk, when they were sacrificed and the retinal tissues were extracted and analyzed for PUFA content by gas‐liquid chromatography. Fatty acid analyses of the retinal phospholipids of the four‐week‐old animals revealed that the group fed DHA (from the fish oil) had the highest level of DHA (32%), compared with values of 19 and 13% for the groups fed canola oil diet and commercial diet, respectively, and 2% for the group fed the diet deficient in n−3 PUFA. The levels of 22∶5n−6 in the retinal lipids were inversely related to the DHA values, being 0.6, 6.6, 11.4, and 20.6 for the fish oil, canola oil, commercial diet, and safflower oil diet groups, respectively. The long‐chain PUFA profiles in the brain phospholipids of the four‐week‐old group were similar to those from the retina. The retinal PUFA values for the eight‐week‐old animals were similar to the four‐week‐old group. The safflower oil diet induced a greater deficit of DHA in retinal lipids than has been reported in rats and monkeys fed similar diets. The guinea pigs fed the commercial diet had retinal and brain PUFA patterns similar to that produced by n−3 PUFA‐deficient diets in rats and monkeys. Guinea pigs fed the canola oil diet had significantly greater retinal DHA levels than those fed the commercial diet, but lower than those fed fish oil. The data suggest that the guinea pig has a reduced capacity for DHA synthesis from α‐linolenic acid as compared with other mammals. Supplementation of guinea pig diets with fish oil produced high retinal and brain DHA levels and prevented the accumulation of 22∶5n−6.
Elongation predominates over desaturation in the metabolism of 18∶3n−3 and 20∶5n−3 in turbot (Scophthalmus maximus) brain astroglial cells in primary culture
Authors: Tocher Dauglas R. 
Published: November 2006

AbstractThe origin of docosahexaenoic acid (DHA, 22∶6n−3) that accumulates in turbot brain during development was investigated by studying the incorporation and metabolismvia the desaturase/elongase pathways of [1‐14C]‐labelled polyunsaturated fatty acids (PUFA) in primary cultures of brain astrocytic glial cells. There was little specificity evident in the total incorporation of PUFAs into the turbot astrocytes. However, specificity was apparent in the distribution of the various PUFAs among the individual lipid classes. In particular, there was very specific incorporation of [14C]arachidonic acid (AA, 20∶4n−6) into phosphatidylinositol balanced by a lower incorporation of this acid into total diradyl glycerophosphocholines. [14C]‐Linolenic acid (LNA, 18∶3n−3) and [14C]eicosapentaenoic acid (EPA, 20∶5n−3) were metabolizedvia the desaturase/elongase pathways to a significantly greater extent than [14C]linoleic acid (18∶2n−6) and [14C]AA. The turbot astrocytes expressed very little Δ5 desaturase activity and only low levels of Δ4 desaturation activity. Although the percentages were small, approximately 4–5 times as much labelled DHA was produced from [14C]EPA compared with [14C]LNA. However, it was concluded that very little DHA in the turbot brain could result from the metabolism of LNA and EPA in astrocytic glial cells.
Relationship between mouse liver Δ9 desaturase activity and plasma lipids
Authors: de Antueno Roberto J. , Cantrill Richard C. , Huang Yung‐Sheng , Elliot Michele , Horrobin David F. 
Published: November 2006

AbstractThis study was undertaken to investigate the total plasma fatty acid composition and the relationship between plasma triacylglycerol (TG) levels and liver Δ9 desaturase activity in mice fed n−3 and/or n−6 fatty acid or hydrogenated coconut oil (HCO) (maximum 25 mg/g) supplemented diets. Generally, plasma TG levels and Δ9 desaturase activity were inversely correlated with the ratio of the sum of long chain n−3 fatty acids to 18∶2n−6 and to the ratio of the sum of long chain n−3 fatty acids to 18∶n−3, but they were positively correlated with the ratio of products and substrates (18∶1/18∶0) of the enzyme in plasma total lipids. The n−3 fatty acid (mainly 20∶5n−3) enriched diet, when compared to the HCO diet at 21 d, caused a significant reduction in plasma TG levels but not in Δ9 desaturase activity. However, a marked reduction in plasma TG content (50–60%) and Δ9 desaturase activity (55–70%) was observed when both 20∶5n−3 and 18∶3n−6 were supplemented in the diet. The plasma TG levels and Δ9 desaturase activity rose again when the animals were fed the HCO diet or chow. The results suggest that low dose supplementation of a mixture of n−3 (mainly 20∶5n−3) and n−6 (18∶3n−6) fatty acids modified both plasma TG content and liver Δ9 desaturase activity, in parallel.
Age‐related changes in Δ6 and Δ5 desaturase activities in rat liver microsomes
Authors: Maniongul C. , Blond J. P. , Ulmann L. , Durand G. , Poisson J. P. , Bézard J. 
Published: November 2006

AbstractAge‐related changes in Δ6 desaturation of [1‐14C]α‐linolenic acid and [1‐14C]linoleic acid and in Δ5 desaturation of [2‐14C]dihomo‐γ‐linolenic acid were studied in liver microsomes from Wistar male rats at various ages ranging from 1.5 to 24 mon. Desaturase activities were expressed both as specific activity of liver microsomes and as the capacity of whole liver to desaturate by taking into account the total amount of liver microsomal protein. Δ6 Desaturation of α‐linolenic acid increased from 1.5 to 3 mon and then decreased linearly up to 24 mon to reach the same desaturation capacity of liver measured at 1.5 mon. The capacity of liver to desaturate linoleic acid increased up to 6 mon and then remained constant, whereas microsomal specific activity was equal at 1.5 and 24 mon of age. The capacity of liver to convert dihomo‐γ‐linolenic acid to arachidonic acid by Δ5 desaturation decreased markedly from 1.5 to 3 mon. It then increased to reach, at 24 mon, the same level as that observed at 1.5 mon. Age‐related changes in the fatty acid composition of liver microsomal phospholipids at the seven time points studied and of erythrocyte lipids at 1.5 and 24 mon were consistent with the variations in desaturation capacity of liver. In particular, arachidonic acid content in old rats was slightly higher than in young rats whereas contents in linoleic and docosahexaenoic acids varied little throughout the life span. The results suggest that, in liver, the activity of desaturases may be regulated in the course of aging to maintain a constant level of polyunsaturated fatty acids in cellular membranes.
Conversion of 13(S)‐hydroperoxy‐9(Z),11(E)‐octadecadienoic acid to the corresponding hydroxy fatty acid by KOH: A kinetic study
Authors: Simpson Thomas D. , Gardner Harold W. 
Published: November 2006

AbstractTransformation of 13(S)‐hydroperoxy‐9(Z),11(E)‐octadecadienoic acid (13S‐HPOD) to 13(S)‐hydroxy‐9(Z),11(E)‐octadecadienoic acid (13S‐HOD) under alkaline conditions (0.05 to 5 M KOH) occurred first‐order with respect to 13S‐HPOD concentration. Overall yield was about 80%. The energy of activation at higher concentrations (3.75 to 5 M KOH) was determined to be in the range of 15.3 to 15.6 kcal. Compared to the 13S‐HPOD conversion, 13(S)‐hydroperoxy‐9(Z),11(E),15(Z)‐octadecatrienoic acid (13S‐HPOT) was converted at a faster rate to the corresponding hydroxy fatty acid (13S‐HOT), with the reaction also being first‐order. Chiral phase high‐performance liquid chromatography demonstrated that in the transformation the stereochemistry of both the 13S‐HPOD and 13S‐HPOT reactants was preserved. Manometric analyses of the KOH/13S‐HPOD reaction showed an uptake of gas, which amounted to 11% of the mols of reactant 13S‐HPOD on the assumption that the gas was O2. As there is a theoretical loss of 1 oxygen atom in the reaction, the fate of this oxygen (possiblyvia active oxygen species) may involve reaction with 13S‐HPOD/13SHOD to form the 20% by‐products.
Identification of core aldehydes amongin vitro peroxidation products of cholesteryl esters
Authors: Kamido H. , Kuksis A. , Marai L. , Myher J. J. 
Published: November 2006

AbstractSynthetic cholesteryl 5‐oxovalerate and 9‐oxononanoate were used as reference standards for the isolation and identification of cholesteryl ester core aldehydes fromtert‐butyl hydroperoxide/Fe++ oxidation of synthetic and natural cholesteryl esters. The core aldehydes were recovered from the peroxidation products by thin‐layer chromatography as the free aldehydes or the 2,4‐dinitrophenylhydrazones and were identified, respectively, by gas‐liquid chromatography (GLC) and by GLC combined with mass spectrometry (GC/MS) or by reverse‐phase high‐performance liquid chromatography (HPLC) and by HPLC with MS (LC/MS). The core aldehydes produced by peroxidation of cholesteryl linoleate were identified as mainly 9‐oxononanoates of cholesterol and oxycholesterols, with smaller amounts of the 8‐oxooctenoates, 10‐oxodecenoates, 11‐oxoundecenoates and 12‐oxododecenoates. Peroxidation of cholesteryl arachidonate yielded 5‐oxovalerates of cholesterol and the oxycholesterols as the main products with smaller amounts of the 4‐oxobutyrates, 6‐oxohexenoates, 7‐oxoheptenoates, 8‐oxooctenoates, 9‐oxononenoates, 9‐oxononadienoates and 10‐oxodecadienotes. The oxycholesterols resulting from the peroxidation of the steroid ring were identified as mainly 7‐keto‐, 7α‐hydroxy‐ and 7β‐hydroxy‐cholesterols and 5α, 6α‐and 5β,6β‐epoxy‐cholestanols. Cholesteryl palmitate and oleate did not yield core aldehydes in the present peroxidation system. In these esters, the sterol and linoleic acid moieties appeared to be oxygenated at about the same rate, while the arachidonic acid moiety reacted more rapidly than did the sterol moiety.
Characteristics of the thiobarbituric acid reactivity of human urine as a possible consequence of lipid peroxidation
Authors: Kosugi Hiroko , Kojima Takashi , Kikugawa Kiyomi 
Published: November 2006

AbstractA 532 nm red pigment formed in the thiobarbituric acid (TBA) assay of human urine was characterized after separation of the pigment by high‐performance liquid chromatography. The yield of the red pigment was some‐what higher at pH 2 than at pH 5; its development was not inhibited by ethylenediaminetetraacetic acid. The characteristics of the pigment were similar to those of the pigment derived from standard malonaldehyde. The amount of the pigment formed was roughly equal to the content of malonaldehyde derivatives estimated as 1‐(2,4‐dinitrophenyl)pyrazole. Pigment formation was significantly enhanced byt‐butyl hydroperoxide (t‐BuOOH) and ferric ions, which may be due to pigment formed from aldehydes other than malonaldehyde; the presence of these aldehydes was confirmed by the formation of the corresponding 2,4‐dinitrophenylhydrazones. The amount of pigment produced from 24‐h urine samples of 12 healthy subjects was estimated to be 26–95 nmol/kg, and 65–182 nmol/kg in the presence oft‐BuOOH. These values are lower than those for urine of rabbit or rat. The TBA reactivity in the absence and presence oft‐BuOOH of human urine was not related to age or sex. The TBA reactivity of human urine collected in the afternoon and in the evening was higher than that of urine collected in the morning.
Fatty acids in the lipids ofDrosophila heads: Effects of visual mutants, carotenoid deprivation and dietary fatty acids
Authors: Stark William S. , Lin Teng‐Nan , Brackhahn David , Christianson J. Scott , Sun Grace Y. 
Published: November 2006

AbstractLipids ofDrosophila heads were extracted and separated by high‐performance thin‐layer chromatography. Fatty acid compositions of major phospholipids as well as of triglycerides were analyzed by gas‐liquid chromatography. Proportions of the major fatty acids (14∶0, 16∶0, 16∶1, 18∶0, 18∶1, 18∶2, 18∶3) varied depending on the lipid analyzed. Docosahexaenoic acid (22∶6), common in vertebrate photoreceptors and brain, and arachidonic acid (20∶4), a precursor of eicosanoids, were lacking. A comparison of the fatty acid composition of the dietvs. the head suggested thatDrosophila can desaturete but may not be able to elongate fatty acid carbon chains. Fatty acid analyses were carried out after the following visual system alterations: i) the transduction mutant whereno receptorpotential results from a deficit in phospholipase C; ii) an allele ofeyes absent; iii) the mutantouterrhabdomeresabsent which lacks visual pigment and rhabdomeres in the predominant type of compound eye receptor, rhabdomeres 1 through 6; and iv) carotenoid deprivation which reduces opsin and rhabdomere size. We also evaluated aging by comparing newly‐emergedvs. aged wild‐type flies. Alterations in fatty acid composition based on some of these manipulations were found. Based on comparisons between flies reared on media differing in C16 and C18, there is an indication that diet readily affects tissue fatty acid composition.