Lipids
1558-9307
Cơ quản chủ quản: WILEY , John Wiley & Sons Inc.
Lĩnh vực:
Cell BiologyBiochemistryOrganic Chemistry
Các bài báo tiêu biểu
cis-5-olefinic unusual fatty acids in seed lipids of gymnospermae and their distribution in triacylglycerols
Tập 17 - Trang 716-723 - 1982
Open-tubular gas chromatographic analysis of fatty acids in the lipids from the seeds of 20 species of Gymnospermae showed that they all contained nonmethylene-interrupted polyenoic (NMIP) acids as minor components and palmitic, oleic, linoleic and α-linolenic acids as major components. The NMIP acids have an additional 5,6-ethylenic bond in ordinary plant unsaturated fatty acids and the following C2 elongation acids:cis-5,cis-9-octadecadienoic acid (5,9–18∶2) (I); 5,9,12–18∶3 (II); 5,9,12,15–18∶4, 5,11–20∶2, 5,11,14–20∶3 (III); and 5,11,14,17–20∶4 (IV). The main NMIP acids found in neutral lipids are I in two species ofTaxus, II in seven species of Pinaceae, III in two species of Podocarpaceae,Torreya nucifera, Cycas revoluta, andGinkgo biloba, and III and IV in each of three species of Taxodiaceae, and Cupressaceae. The polar lipids constitute the minor fraction of seed lipids in general. The content and composition of NMIP acids in these lipids differe considerably from those in neutral lipids. Analysis of the partial cleavage products of triacylglycerols showed that the NMIP acids distribute mainly in the 1,3-position.
Distribution of Glycolipid and Unsaturated Fatty Acids in Human Hair
Tập 49 - Trang 905-917 - 2014
It has been recognized that human hair lipids play crucial roles in the integrity of cells and matrices, while the details of distribution and structure of the minor lipids are hardly known. Here we investigated the lipids at the hair surface, at the interface between cuticle and cortex and in the interior of hair (cortex, medulla and melanin granules). Hair lipids and fatty acids and their metabolites were detected and characterized by using infrared spectroscopy and several mass spectrometry techniques (FTIR, ToF–SIMS, GCMS, and ESI–MS). As a result, it was found that unsaturated fatty acids were present more in the cortex of hair than at the hair surface. At the interface between cuticle and cortex, it is suggested that steryl glycoside-like lipids containing N-acetylglucosamine were present, and contributing to the adhesion between the cuticle and cortex of hair. Oxidative metabolites derived from integral fatty acids such as linoleic and alpha-linolenic acids were found in the hair bulb and melanin granules. Especially the oxidative metabolites of alpha-linolenic acid were integrated into the lipids non-covalently and tightly bound to melanin granules (namely, melanin lipids) and suggested as being involved in the biosynthetic processes of melanosome.
Genetic variability of human plasma and erythrocyte lipids
Tập 6 - Trang 595-600 - 1971
Genetic variation of fasting plasma lipids, lipoproteins and erythrocyte membrane lipids was studied in 67 sets of like-sexed twins and 3 sets of triplets. All of the plasma lipids were more variable in dizygotic twins than monozygotic twins with the exception of phosphatidyl ethanolamine, but only cholesteryl esters, lecithin, phosphatidyl inositol and β-lipoprotein showed significant genetic variation. In contrast, no significant genetic variability was found in any of the erythrocyte membrane lipids and erythrocyte phosphatidyl ethanolamine had significantly greater variation in monozygotic twins. Two sets of twins had an extra lipoprotein band (slow α1); in one family the variant appeared to be segregating as a dominant trait.
Fatty acid profiles and relative mobilization during fasting in adipose tissue depots of the American marten (<i>Martes americana</i>) Abstract The American marten (Martes americana ) is a boreal forest marten with low body adiposity but high metabolic rate. The study describes the FA composition in white adipose tissue depots of the species and the influence of food deprivation on them. American marten (n =8) were fasted for 2 d with 7 control animals. Fasting resulted in a 13.4% weight loss, while the relative fat mass was >25% lower in the fasted animals. The FA composition of the fat depots of the trunk was quite similar to other previously studied mustelids with 14∶0, 16∶0, 18∶0, 16∶1n−7, 18∶1n−9, and 18∶2n−6 as the most abundant FA. In the extremities, there were higher proportions of monounsaturated FA (MUFA) and PUFA. Food deprivation decreased the proportions of 16∶0 and 16∶1n−7, while the proportion of long‐chain MUFA increased in the trunk. The mobilization of FA was selective, as 16∶1n−7, 18∶1n−9, and particular n−3 PUFA were preferentially mobilized. Relative mobilization correlated negatively with the carbon chain length in saturated FA (SFA) and n−9 MUFA. The Δ9 desaturation of SFA enhanced the mobilization of the corresponding MUFA, but the positional isomerism of the first double bond did not correlate consistently with relative mobilization in MUFA or PUFA. In the marten, the FA composition of the extremities was highly resistant to fasting, and the tail tip and the paws contained more long‐chain PUFA to prevent the solidification of lipids and to maintain cell membrane fluidity during cooling.
Tập 41 Số 3 - 2006
Biosynthesis of 14,15-Hepoxilins in Human L1236 Hodgkin Lymphoma Cells and Eosinophils
Tập 46 - Trang 69-79 - 2010
Hepoxilins are epoxy alcohols synthesized through the 12-lipoxygenase (12-LO) pathway in animal cells. The epidermis is the principal source of hepoxilins in humans. Here we report on the formation of novel hepoxilin regioisomers formed by the 15-LO pathway in human cells. The Hodgkin lymphoma cell line L1236 possesses high 15-lipoxygenase-1 (15-LO-1) activity and incubation of L1236 cells with arachidonic acid led to the formation of 11(S)-hydroxy-14(S),15(S)-epoxy 5(Z),8(Z),12(E) eicosatrienoic acid (14,15-HxA3 11(S)) and 13(R)-hydroxy-14(S),15(S)-epoxy 5(Z),8(Z),11(Z) eicosatrienoic acid (14,15-HxB3 13 (R)). In addition, two hitherto unidentified products were detected and these products were collected and analyzed by positive ion electrospray tandem mass spectrometry. These metabolites were identified as 11(S),15(S)-dihydroxy-14(R)-glutathionyl-5(Z),8(Z),12(E)-eicosatrienoic acid (14,15-HxA3-C) and 11(S),15(S)-dihydroxy-14(R)-cysteinyl-glycyl-5(Z),8(Z),12(E)-eicosatrienoic acid (14,15-HxA3-D). Incubation of L1236 cells with synthetic 14,15-HxA3 11(S) also led to the formation of 14,15-HxA3-C and 14,15-HxA3-D. Several soluble glutathione transferases, in particular GST M1-1 and GST P1-1, were found to catalyze the conversion of 14,15-HxA3 to 14,15-HxA3-C. L1236 cells produced approximately twice as much eoxins as cysteinyl-containing hepoxilins upon stimulation with arachidonic acid. Human eosinophils, nasal polyps and dendritic cells selectively formed 14,15-HxA3 11(S) and 14,15-HxB3 13(R) stereoisomers, but not cysteinyl-containing hepoxilins, after stimulation with arachidonic acid. Furthermore, purified recombinant 15-LO-1 alone catalyzed the conversion of arachidonic acid to 14,15-HxA3 11(S) and 14,15-HxB3 13(R), showing that human 15-LO-1 possesses intrinsic 14,15-hepoxilin synthase activity.
Effects of dietary cholesterol upon bile acid metabolism in guinea pig Abstract Cholesterol fed guinea pigs develop a hemolytic anemia accompanied by high cholesterol concentrations in the liver, plasma, and red cells. We have studied the bile acid metabolism of guinea pigs fed a diet with or without cholesterol in a search for the factor(s) which prevent adequate control of their body cholesterol pool and, therefore, its pathological consequences. The results show that in the cholesterol fed guinea pig the synthesis (and excretion) of bile acids was at least three times greater than in controls. This is the result of a doubling of the fractional turnover rate and a smaller increase in the pool size. The major increase of the bile acid pool was in the liver. The main bile acid in gall bladder bile and small intestines was chenodeoxycholic acid, with smaller amounts of 7‐ketolithocholic and ursodeoxycholic acids. In the caecum, large intestines, and feces, the major bile acid was lithocholic acid.
Tập 9 Số 10 - Trang 731-737 - 1974
Identification of Oxidized Phosphatidylinositols Present in OxLDL and Human Atherosclerotic Plaque
Tập 52 - Trang 11-26 - 2016
Oxidized low-density lipoprotein (OxLDL) plays an important role in initiation and progression of atherosclerosis. Proatherogenic effects of OxLDL have been attributed to bioactive phospholipids generated during LDL oxidation. It is unknown what effect oxidation has on the phosphatidylinositol (PtdIns) molecules in LDL, even though PtdIns is 6% of the total LDL phospholipid pool. We sought to identify and quantitate oxidized phosphatidylinositol (OxPtdIns) species in OxLDL and human atherosclerotic plaque. Bovine liver PtdIns was subjected to non-enzymatic and lipoxygenase-catalyzed oxidation. Reversed-phase liquid chromatography with negative ESI–MS identified and confirmed compounds by fragmentation pattern analysis from which an OxPtdIns library was generated. Twenty-three OxPtdIns molecules were identified in copper-oxidized human LDL at 0, 6, 12, 24, 30, and 48 h, and in human atherosclerotic plaque. In OxLDL, OxPtdIns species containing aldehydes and carboxylates comprised 17.3 ± 0.1 and 0.9 ± 0.2%, respectively, of total OxPtdIns in OxLDL at 48 h. Hydroperoxides and isoprostanes at 24 h (68.5 ± 0.2 and 22.8 ± 0.2%) were significantly greater than 12 h (P < 0.01) without additional changes thereafter. Hydroxides decreased with increased oxidation achieving a minimum at 24 h (5.2 ± 0.3%). Human atherosclerotic plaques contained OxPtdIns species including aldehydes, carboxylates, hydroxides, hydroperoxides and isoprostanes, comprising 18.6 ± 4.7, 1.5 ± 0.7, 16.5 ± 7.4, 33.3 ± 1.1 and 30.2 ± 3.3% of total OxPtdIns compounds. This is the first identification of OxPtdIns molecules in human OxLDL and atherosclerotic plaque. With these novel molecules identified we can now investigate their potential role in atherosclerosis.
Longitudinal Assessment of Erythrocyte Fatty Acid Composition Throughout Pregnancy and Post Partum
Tập 42 - Trang 335-344 - 2007
Transfer of fatty acids from mother to fetus during pregnancy is a requirement for optimal fetal growth. We report a longitudinal study of full maternal erythrocyte fatty acid profile assessed at each trimester of pregnancy [mean 12.5 (range 8–14), 26.1 (24–28) and 35.5 (33–38) weeks’ gestation] and in the post partum period [18.1 (12–26) weeks]. The study recruited healthy women (n = 47) from routine antenatal clinics at the Princess Royal Maternity Unit, Glasgow, Scotland. There were increases in 16:1n7 (22%, p = 0.0005), 24:1n9 (13%, p = 0.0032), 22:5n6 (25%, p = 0.0003), 18:3n3 (41%, p = 0.0007) and 22:6n3 (20%, p = 0.0005) concentrations during pregnancy. The greatest increases took place between gestations at sampling of 12.5 and 26.1 weeks. The change in 16:1n7 concentration between gestations at sampling of 12.5 and 35.3 weeks was negatively associated with maternal booking body mass index (r = −0.40, p = 0.006). The change in 22:6n3 concentration was correlated with the change in 24:1n9 (r = 0.70, p < 0.001). In samples taken four months post partum, 14:0 concentration was lower (29%, p = 0.0002) and 24:0 concentration (15%, p = 0.0009) and n6/n3 ratio (11%, p = 0.0019) were higher than at a gestation at sampling of 12.5 weeks. In conclusion, several fatty acids are specifically mobilised during pregnancy. The correlation between maternal 22:6n3 and 24:1n9 suggests that mobilisation of these fatty acids may be coordinated. The inverse relationship between 16:1n7 and maternal central obesity warrants further investigation.
The female docosahexaenoic acid status related to the number of completed pregnancies
Tập 34 - Trang S229-S229 - 1999
Differences in the long chain (sphingoid) base composition of sphingomyelin from rats bearing Morris hepatoma 7777
Tập 21 - Trang 529-530 - 1986
The long chain bases of sphingomyelin from Morris hepatoma 7777 and host and control livers were analyzed by capillary gas liquid chromatography. Sphingosine (18∶1) was the major long chain base of control livers (66.5%) and hepatomas (65.6%), but hepatomas also had a high percentage (9.3 vs 4.4) of the 16∶1 homolog. Host liver had the most unusual long chain base composition, with ca. equal 16∶1 (24.4%) and 18∶1 (21.4%) and high amounts of 20-carbon bases (9.2% 20∶0 and 15.3% 20∶1). These differences may be related to the aberrant fatty acid metabolism known to occur in tumor-bearing animals. Such large perturbations in the long chain base composition of hepatic sphingomyelin are unprecedented and could have a major impact on the properties of host membranes.