bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fatty acid analysis of blood serum, seminal plasma, and spermatozoa of normozoospermic vs. Asthernozoospermic males
Authors: Conquer Julie A. , Martin James B. , Tummon Ian , Watson Lynn , Tekpetey Francis 
Published: November 2006

AbstractDocosahexaenoic acid (DHA; 22∶6n−3) is found in extremely high levels in human ejaculate with the majority occurring in the spermatozoa. However, the relative concentration of DHA and other fatty acids, in blood serum, seminal plasma, and spermatozoa of asthenozoospermic vs. normozoospermic individuals is not known. We analyzed the phospholipid fatty acid composition of blood serum, seminal plasma, and spermatozoa of normozoospermic men and asthenozoospermic men in order to determine if DHA levels, as well as the levels of other fatty acids, differed. The serum phospholipid DHA levels were similar in the two groups, suggesting similar intakes of dietary DHA. On the other hand, seminal plasma levels of DHA (3.0 vs. 3.7%) and total polyunsaturated fatty acids (PUFA) (11.8 vs. 13.5%) were significantly lower in asthenozoospermic vs. normozoospermic men, respectively, while 18∶1 (19.0 vs. 16.8%) and monounsaturated fatty acids (MUFA) (24.2 vs. 21.7%) were significantly higher in the asthenozoospermic vs. the normozoospermic men. Spermatozoa from asthenozoospermic men had higher levels of 18∶1, 20∶0, 22∶0, 22∶1, and 24∶0 than sperm from normozoospermic men, and lower levels of 18∶0 and DHA (8.2 vs. 13.8%). Furthermore, total MUFA (19.3 vs. 16.5%) was higher and total PUFA (19.0 vs. 24.0%), n−3 fatty acids (9.3 vs. 14.6%), and the ratio of n−3 to n−6 fatty acids (1.0 vs. 1.6) were lower in the asthenozoospermic men. Therefore, in asthenozoospermic individuals, lower levels of DHA in the seminal plasma, but not in the blood serum, mimic the decreased concentrations of DHA in the spermatozoa. This suggests that the lower concentrations of spermatozoon DHA in these individuals are due not to dietary differences but to some type of metabolic difference in the asthenozoopermic men.
Apolipoprotein B mRNA editing and apolipoprotein gene expression in the liver of hyperinsulinemic fatty zucker rats: Relationship to very low density lipoprotein composition
Authors: Elam Marshall B. , von Wronski Matthew A. , Cagen Lauren , Thorngate Fayanne , Kumar Poonam , Heimberg Murray , Wilcox Henry G. 
Published: November 2006

AbstractWe previously demonstrated increased apolipoprotein B (apoB) mRNA editing, elevated levels of mRNA for the catalytic component of the apoB mRNA editing complex, apobec‐1, and increased secretion of the product of the edited mRNA, apoB48, in very low density lipoproteins (VLDL) in primary cultures of Sprague‐Dawley rat hepatocytes following insulin treatment. In order to determine the effect of in vivo hyperinsulinemia on these processes, we determined apoB mRNA editing, apobec‐1 expression, hepatic expression of mRNA for apoB and other VLDL apoproteins, and the quantity and composition of plasma VLDL in the hyperinsulinemic fatty Zucker rat. Total apoB mRNA content of the livers of the fatty rats and lean littermates did not differ, however, edited apoB message coding for hepatic apo B48, and abundance of mRNA for the catalytic subunit of the apoB mRNA editing complex, apobec‐1, was increased by 1.7‐and 3.3‐fold, respectively, in fatty rats. ApoCIII mRNA abundance was increased in livers of fatty rats as well, but the abundance of hepatic apoE mRNA in the fatty animal was not different from that of the lean rat. Hepatic apoAI mRNA abundance was also increased in the fatty rats. Associated with increased apoB mRNA editing, was the 1.7‐fold increase in the fraction of apoB in plasma as apoB48 in fatty rats. VLDL‐triglyceride and‐apoB in plasma were 15‐and 3‐fold higher, respectively, in fatty Zucker rats compared to lean littermates, indicating both enrichment of VLDL with triglycerides and increased accumulation of VLDL particles. Increased hepatic expression of mRNA for apoCIII and apoAI was associated with increased content of apoC (and relative depletion of apoE) in VLDL of fatty rats, and plasma apoAI was increased in fatty Zucker rats, primarily in the HDL fraction. The current study provides further evidence that chronic exposure to high levels of insulin influences both the quantity of and lipid/apoprotein composition of VLDL in plasma. The increased apoC and decreased apoE (as well as increased triglyceride) content of VLDL in the fatty Zucker rat observed in the current study may affect VLDL clearance and therefore may be a factor in the observed accumulation of VLDL in the plasma of the fatty hyperinsulinemic Zucker rats.
Characterization of the ybdT gene product of Bacillus subtilis: Novel fatty acid β‐hydroxylating cytochrome P450
Authors: Matsunaga Isamu , Ueda Atsuo , Fujiwara Nagatoshi , Sumimoto Tatsuo , Ichihara Kosuke 
Published: November 2006

AbstractWe have characterized the gene encoding fatty acid α‐hydroxylase, a cytochrome P450 (P450) enzyme, from Sphingomonas paucimobilis. A database homology search indicated that the deduced amino acid sequence of this gene product was 44% identical to that of the ybdT gene product that is a 48 kDa protein of unknown function from Bacillus subtilis. In this study, we cloned the ybdT gene and characterized this gene product using a recombinant enzyme to clarify function of the ybdT gene product. The carbon monoxide difference spectrum of the recombinant enzyme showed the characteristic one of P450. In the presence of H2O2, the recombinant ybdT gene product hydroxylated myristic acid to produce β‐hydroxyristic acid and α‐hydroxymyristic acid which were determined by high‐performance liquid chromatography (HPLC) and gas chromatography‐mass spectrometry. The amount of these products increased with increasing reaction period and amount of H2O2 in the reaction mixture. The amount of β‐hydroxyl product was slightly higher than that of α‐hydroxyl product at all times during the reaction. However, no reaction products were detected at any time or at any concentration of H2O2 when heat‐inactivated enzyme was used. HPLC analysis with a chiral column showed that the β‐hydroxyl product was nearly enantiomerically pure R‐form. These results suggest that this P450 enzyme is involved in a novel biosynthesis of β‐hydroxy fatty acid.
Identification of acylated glycoglycerolipids from a cyanobacterium, Synechocystis sp., by tandem mass spectrometry
Authors: Kim Young Hwan , Choi Jong‐Soon , Hong Jongki , Yoo Jong Shin , Kim Myung Soo 
Published: November 2006

AbstractAcylated glycoglycerolipids were identified in the total lipid extract from cyanobacerium Synechocystis sp. PCC 6803. These compounds have a palmitoyl group esterified to the hydroxyl group at the C‐6 position of the terminal glycosyl moiety of digalactosyl monoacylglycerol and digalactosyl diacylglycerol. Their structural elucidation was accomplished by tandem mass spectrometry coupled with fast atom bombardment ionization. Acylated digalactosyl monoacylglycerol has a structure of 1‐hydroxy‐2‐palmitoyl‐3‐O‐[(6‐O‐palmitoyl)‐α‐d‐galactopyranosyl‐(1→6)‐β‐d‐galactopyranosyl]‐sn‐glycerol. This compound has not been reported previously.
Δ5‐Olefinic acids in the seed lipids from four Ephedra species and their distribution between the α and β positions of triacylglycerols. Characteristics common to coniferophytes and cycadophytes
Authors: Wolff Robert L. , Christie William W. , Pédrono Frédérique , Marpeau Anne M. , Tsevegsüren Nanzad , Aitzetmüller Kurt , Gunstone Frank D. 
Published: November 2006

AbstractThe fatty acid compositions of the seed lipids from four Ephedra species, E. nevadensis, E. viridis, E. przewalskii, and E. gerardiana (four gymnosperm species belonging to the Cycadophytes), have been established with an emphasis on Δ5‐unsaturated polymethylene‐interrupted fatty acids (Δ5‐UPIFA). Mass spectrometry of the picolinyl ester derivatives allowed characterization of 5,9‐ and 5,11–18∶2; 5,9,12–18∶3; 5,9,12,15–18∶4; 5,11–20∶2; 5,11,14–20∶3; and 5,11,14,17–20∶4 acids. Δ5‐UPIFA with a Δ11‐ethylenic bond (mostly C20 acids) were in higher proportions than δ5‐UPIFA with a δ9 double bond (exclusively C18 acids) in all species. The total δ5‐UPIFA content was 17–31% of the total fatty acids, with 5, 11, 14–20∶3 and 5, 11, 14, 17–20∶4 acids being the principal δ5‐UPFIA isomers. The relatively high level of cis‐vaccenic (11–18∶1) acid found in Ephedra spp. seeds, the presence of its δ5‐desaturation product, 5, 11–18∶2 acid (proposed trivial name: ephedrenic acid), and of its elongation product, 13–20∶1 acid, were previously shown to occur in a single other species, Ginkgo biloba, among the approximately 170 gymnosperm species analyzed so far. Consequently, Ephedraceae and Coniferophytes (including Ginkgoatae), which have evolved separately since the Devonian period (≈300 million yr ago), have kept in common the ability to synthesize C18 and C20 δ5‐UPIFA. We postulate the existence of two δ5‐desaturases in gymnosperm seeds, one possibly specific for unsaturated acids with a δ9‐ethylenic bond, and the other possibly specific for unsaturated acids with a δ11‐ethylenic bond. Alternatively, the δ5‐desaturases might be specific for the chain length with C18 unsaturated acids on the one hand and C20 unsaturated acids on the other hand. The resulting hypothetical pathways for the biosynthesis of δ5‐UPIFA in gymnosperm seeds are only distinguished by the position of 11–18∶1 acid. Moreover, 13C nuclear magnetic resonance spectroscopy of the seed oil from two Ephedra species has shown that δ5‐UPIFA are essentially excluded from the internal position of triacylglycerols, a characteristic common to all of the Coniferophytes analyzed so far (more than 30 species), with the possibility of an exclusive esterification at the sn‐3 position. This structural feature would also date back to the Devonian period, but might have been lost in those rare angiosperm species containing δ5‐UPIFA.
Preparation, separation, and confirmation of the eight geometrical cis/trans conjugated linoleic acid isomers 8,10‐through 11,13–18∶2
Authors: Eulitz Klaus , Yurawecz Martin P. , Sehat Najibullah , Fritsche Jan , Roach John A. G. , Mossoba Magdi M. , Kramer John K. G. , Adlof Richard O. , Ku Yuoh 
Published: November 2006

AbstractConjugated linoleic acid (CLA) mixtures were isomerized with p‐toluenesulfinic acid or I2 catalyst. The resultant mixtures of the eight cis/trans geometric isomers of 8,10‐, 9,11‐, 10,12‐, and 11,13‐octadecadienoic (18∶2) acid methyl esters were separated by silver ion‐high‐performance liquid chromatography (Ag+‐HPLC) and gas chromatography (GC). Ag+‐HPLC allowed the separation of all positional CLA isomers and geometric cis/trans CLA isomers except 10,12–18∶2. However, one of the 8,10 isomers (8cis, 10trans‐18∶2) coeluted with the 9trans,11cis18∶2 isomer. There were differences in the elution order of the pairs of geometric CLA isomers resolved by Ag+‐HPLC. For the 8,10 and 9,11 CLA isomers, cis,trans eluted before trans,cis, whereas the opposite elution pattern was observed for the 11,13–18∶2 geometric isomers (trans,cis before cis,trans). All eight cis/trans CLA isomers were separated by GC on long polar capillary columns only when their relative concentrations were about equal. Large differences in the relative concentration of the CLA isomers found in natural products obscured the resolution and identification of a number of minor CLA isomers. In such cases, GC‐mass spectrometry of the dimethyloxazoline derivatives was used to identify and confirm coeluting CLA isomers. For the same positional isomer, the cis,trans consistently eluted before the trans,cis CLA isomers by GC. High resolution mass spectrometry (MS) selected ion recording (SIR) of the molecular ions of the 18∶1 18∶2, and 18∶3 fatty acid methyl esters served as an independent and highly sensitive method to confirm CLA methyl ester peak assignments in GC chromatograms obtained from food samples by flame‐ionization detection. The high‐resolution MS data were used to correct for the nonselectivity of the flame‐ionization detector.
Mechanisms mediating lipoprotein responses to diets with medium‐chain triglyceride and lauric acid
Authors: Tsai Yu‐Hwai , Park Sunmin , Kovacic Jeffery , Snook Jean T. 
Published: November 2006

AbstractMedium‐chain triglycerides (MCT) are often used in specialized formula diets or designer fats because of their special properties. Yet their influence on lipid metabolis is not completely understood. In this two‐period cross‐over study, the effects of MCT (8∶0+10∶0) in contrast to a similar saturated fatty acid (12∶0) were compared. Eighteen healthy women ate a baseline diet [polyunsaturated (PUFA)/saturated fat=0.9] fer 1 wk. Then, they consumed test diets (PUFA/saturated fat=0.2) for 4 wk. Monounsaturated fat and cholesterol were constant in baseline and treatment diets. MCT and 12∶0, substituted for part of the PUFA, provided 14 energy (en)% of the test diets. In comparison to the PUFA baseline diet, a 16% increase in mean serum low density lipoprotein (LDL)‐cholesterol (C) on the 12∶0 diet was accompanied by a 21% decrease in mean receptormediated degradation of LDL by freshly isolated mononuclear cells (MNC) in vitro. The MNC assay theoretically gives an indication of receptor‐mediated degradation of LDL. In contrast, the MCT diet raised mean receptor‐mediated degradation of LDL by 42%, a finding out of line with the mean 11% increase in serum LDL‐C. Perhaps MCT, by increasing the rate of LDL‐C production, overcame the rate of LDL‐C clearance. The 12∶0 diet enhanced some factors involved in reverse cholesterol transport (e.g., high density lipoprotein fractions) while MCT had a different of less pronounced effect. The overall effects of MCT on cholesterol metabolism may or may not be desirable, whereas those of 12∶0 appear largely undesirable as previously reported.
Eicosapentaenoic acid and docosahexaenoic acid selectively attenuate U46619‐induced smooth muscle cell proliferation
Authors: Pakala Rajbabu , Pakala Rajashree , Benedict Claude 
Published: November 2006

AbstractIt is well known that vascular smooth muscle cell (SMC) proliferation is a key step in atheromatous plaque formation. Thromboxane A2 (T×A2), released from aggregating platelets and an injured vessel wall, may play an important role in the development of atheromatous plaque. Many animal studies have suggested that n−3 polyunsaturated fatty acids eicosapentaenoic acid (EPA, 20∶5n−3) and docosahexaenoic acid (DHA, 22∶6n−3) present in the fish oils have antiatherosclerotic effects. In the present study, we investigated the effect of EPA and DHA on I×A2‐induced SMC proliferation. To determine the functional selectivity of n−3 fatty acids, we also tested the effect of arachidonic acid (AA, 20∶4n−6), γ‐linolenic acid) (INA, 18∶3n−6), and oleic acid (OA, 18∶1n−9) on T×A2‐induced SMC proliferation. Only LPA and DHA prevented the SMC proliferation induced by the T×A2 mimetic U46619. When EPA and DHA were added together in the ratio in which they are present in menhaden oil, EPA and DHA acted synergistically to block the SMC proliferation induced by the TXA2‐mimetic. These findings suggest that the n−3 polyunsaturated fatty acids in fish oils may exert antiatherosclerotic effects by blocking the mitogenstimulated proliferation of SMC.
Induction of apoptosis and apoptotic mediators in balb/C splenic lymphocytes by dietary n−3 and n−6 fatty acids
Authors: Avula C. P. Reddy , Zaman A. K. , Lawrence R. , Fernandes G. 
Published: November 2006

AbstractThe present study was designed to investigate the effect of diatery n−6 and n−3 polyunsaturated fatty acids (PUFA) on anti‐CD3 and anti‐Fas antibody‐induced apoptosis and its mediators in mouse spleen cells. Nutritionally adequate semipurified diets containing either 5% w/w corn oil (n−6 PUFA) or fish oil (n−3 PUFA) were fed to weanling female Balb/C mice, and 24 wk later mice were sacrificed. In n−3 PUFA‐fed mice, serum and splenocyte lipid peroxides were increased by 20 and 28.3% respectively, compared to n−6 PUFA‐fed mice. Further, serum vitamin F levels were decreased by 50% in the n−3 PUFA‐fed group, whereas higher anti0Fas‐ and anti‐CD3‐induced apoptosis (65 and 66%) and necrosis (17 and 25%), compared to the n−6 PUFA‐fed group, were found when measured with Annexin V and propidium iodide staining, respectively. In addition, decreased Bcl‐2 and increased Fas‐ligand (Fas‐L) also were observed in the n−3 PUFA‐fed group compared to the n−6 PUFA‐fed group. No difference in the ratio of splenocyte subsets nor their Fas expression was observed between the n−3 PUFA‐fed and n−6 PUFA‐fed groups, whereas decreased proliferation of splenocytes was found in n−3 PUFA‐fed mice compared to n−6 PUFA‐fed mice. In conclusion, our results indicate that dietary n−3 PUFA induces higher apoptosis by increasing the generation of lipid peroxides and elevating Fas‐L expression along with decreasing Bcl‐2 expression. A reduced proliferative response of immune cells also was observed in n−3 PUFA‐fed mice.
Eicosapentaenoic and docosahexaenoic acid affect mitochondrial and peroxisomal fatty acid oxidation in relation to substrate preference
Authors: Madsen Lise , Rustan Arild C. , Vaagenes Hege , Berge Kjetil , Dyrøy Endre , Berge Rolf K. 
Published: November 2006

AbstractDecreased triacylglycerol synthesis within hepatocytes due to decreased diacylglycerol acyltransferase (DGAT) activity has been suggested to be an important mechanism by which diets rich in fish oil lower plasma triacylglycerol levels. New findings suggest that eicosapentaenoic acid (EPA), and not docosahexaenoic acid (DHA), lowers plasma triacylglycerol by increased mitochondrial fatty acid oxidation and decreased availability of fatty acids for triacylglycerol synthesis. To contribute to the understanding of the triacylglycerol‐lowering mechanism of fish oil, the different metabolic properties of EPA and DHA were studied in rat liver parenchymal cells and isolated rat liver organelles. EPA‐CoA was a poorer substrate than DHA‐CoA for DGAT in isolated rat liver microsomes, and in the presence of EPA, a markedly lower value for the triacyl[3H]glycerol/diacyl[3H]glycerol ratio was observed. The distribution of [1‐14C]palmitic acid was shifted from incorporation into secreted glycerolipids toward oxidation in the presence of EPA (but not DHA) in rat liver parenchymal cells. [1‐14C]EPA was oxidized to a much greater extent than [1‐14C]DHA in rat liver parenchymal cells, isolated peroxisomes, and especially in purified mitochondria. As the oxidation of EPA was more effective and sensitive to the CPT‐I inhibitor, etomoxir, when measured in a combination of both mitochondria and peroxisomes, we hypothesized that both are involved in EPA oxidation, whereas DHA mainly is oxidized in peroxisomes. In rats, EPA treatment lowered plasma triacylglycerol and increased hepatic mitochondrial fatty acid oxidation and carnitine palmitoyltransferase (CPT)‐I activity in both the presence and absence of malonyl‐CoA. Whereas only EPA treatment increased the mRNA levels of CPT‐I, DHA treatment increased the mRNA levels of peroxisomal fatty acyl‐CoA oxidase and fatty acid binding protein more effectively than EPA treatment. In conclusion, EPA and DHA affect cellular organelles in relation to their substrate preference. The present study strongly supports the hypothesis that EPA, and not DHA, lowers plasma triacylglycerol by increased mitochondrial fatty acid oxidation.
Effects of conjugated linoleic acid isomers on the hepatic microsomal desaturation activities in vitro
Authors: Bretillon L. , Chardigny J. M. , Grégoire S. , Berdeaux O. , Sébédio J. L. 
Published: November 2006

AbstractThe influence of individual conjugated linoleic acid (CLA) isomers on the Δ6 desaturation of linoleic and α‐linolenic acids and on the Δ9 desaturation of stearic acid was investigated in vitro, using rat liver microsomes. The Δ6 desaturation of 18∶2n−6 was decreased from 23 to 38% when the ratio of 9cis,11trans‐18∶2 to 18∶2n−6 increased from 0.5 to 2. The compound 10trans,12cis‐18∶2 exhibited a similar effect only at the highest concentration. The Δ6 desaturation of α‐linolenic acid was slightly affected by the presence of CLA isomers. The sole isomer to induce an inhibitory effect on the Δ9 desaturation of stearic acid was 10trans,12cis‐18∶2.
Dietary conjugated linoleic acid reciprocally modifies ketogenesis and lipid secretion by the rat liver
Authors: Sakono Masanobu , Miyanaga Fumiko , Kawahara Satoshi , Yamauchi Kiyoshi , Fukuda Nobuhiro , Watanabe Kazumasa , Iwata Toshio , Sugano Michihiro 
Published: November 2006

AbstractThe effects of dietary conjugated linoleic acid (CLA) and linoleic acid (LA) on ketone body production and lipid secretion were compared in isolated perfused rat liver. After feeding the 1% CLA diet for 2 wk, the concentration of post‐perfused liver cholesterol was significantly reduced by CLA feeding, whereas that of triacylglycerol remained unchanged. Livers from CLA‐fed rats produced significantly more ketone bodies; and the ratio of β‐hydroxybutyrate to acetoacetate, an index of mitochondrial redox potential, tended to be consistently higher in the liver perfusate. Conversely, cumulative secretions of triacylglycerol and cholesterol were consistently lower in the livers of rats fed CLA, and the reduction in the latter was statistically significant. Thus dietary CLA appeared to exert its hypolipidemic effect at least in part through an enhanced β‐oxidation of fatty acids at the expense of esterification of fatty acid in the liver.
Effects of conjugated linoleic acid on oxygen diffusion‐concentration product and depletion in membranes by using electron spin resonance spin‐label oximetry
Authors: Yin Jun Jie , Mossoba Magdi M. , Kramer John K. G. , Yurawecz Martin P. , Eulitz Klaus , Morehouse Kim M. , Ku Yuoh 
Published: November 2006

AbstractThe effect of conjugated linoleic acid (CLA) on the relation between structure and function of membranes is described in this paper. Electron spin resonance (ESR) spin‐label oximetry was used in the present study to evaluate if oxygen transport and oxygen depletion were affected by incorporation of CLA instead of linoleic acid into membrane phospholipids. Specifically, 1‐stearoyl‐2(9 cis, 11 trans‐octadecadienoyl)‐phosphorylcholine (SCLAPC) was incorporated into soy plant phosphatidylcholine (soy PC) or egg yolk PC (EYPC) bilayers. The use of spin labels attached to different carbons along the fatty acid chain makes it possible to carry out structural and oximetric determinations with the same test sample. For example, the incorporation of 5 mol% SCLAPC increased the oxygen diffusion‐concentration product in soy PC or EYPC liposomes at 37°C, slightly decreased the ordering of the hydrocarbon chains at the C10 and C12 positions (in the region of the conjugated double bonds), and increased the rate of oxygen depletion from the aqueous medium. Similar results were not obtained by incorporating 5 mol% of 1‐stearoyl‐2‐linoleoyl‐PC (SLPC). In our model system, free‐radical generation was initiated by extended incubation of the liposomes, by induction by 2,2′‐azobis(2‐amidinopropane)hydrochloride, or by ultraviolet irradiation of H2O2. The rate of consumption of molecular oxygen was studied by monitoring the oxygen concentration in the aqueous phases of the liposomes. The effect of 5 mol% SCLAPC in soy PC was significantly larger than 5 mol% SLPC in soy PC; the response patterns with soy PC and EYPC were similar. Furthermore, 5 mol% SCLAPC in 1‐palmitoyl‐2‐linoleoyl‐PC showed similar oxygen consumption to that observed with 5 mol% SCLAPC in EYPC. On the other hand, 5 mol% SCLAPC in synthetic PC membranes containing saturated or monounsaturated fatty acids showed low oxygen depletion rates. The perturbation of membrane structure and the increase of the relative oxygen diffusion‐concentration products provided a potential mechanism by which CLA incorporated into membrane lipids could affect oxidative stress.