bluuebunny/crossref_metadata_2025_split huggingface dataset:
Purification and characterization of a fatty acid binding protein from human prostatic tissue
Authors: Chaudry Aziz A. , Dutta‐Roy Asim K. 
Published: November 2006

AbstractEpidemiological studies suggest the existence of a strong relationship between the incidence of prostatic cancer and the intake of dietary lipids in humans. However, very little information is available on intracellular fatty acid metabolism in human prostatic tissue. The objective of this study was to identify and subsequently characterize a fatty acid binding protein of human prostatic tissue. A fatty acid binding protein (FABP) was purified and characterized from human prostatic tissue. The purified FABP had an apparent molecular mass of 15.0±1.0 kDa as averaged from three different methods, sodium dodecylsulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE), gel filtration and amino acid analysis. The pI value of the protein was determined to be 6.8. Scatchard analysis of fatty acid binding to the purified FABP from malignant prostatic tissue showed a Kd value of 0.53±0.02 μM for arachidonic acid (n=5). The Kd values of FABP purified from benign prostatic tissue were 0.57±0.02 μM for oleic acid and 0.51±0.04 μM for arachidonic acid (n=5). Fatty acid analysis revealed that the level of endogenously bound arachidonic acid was about 2.5‐fold higher in FABP from malignant than from benign tissue. In addition, both malignant and benign tissues contained the same concentration of FABP. The concentrations of FABP in malignant and benign tissues were 19.2±1.8 and 21.4±2.1 μg per mg of total cytosolic protein, respectively. Characterization based on amino acid composition, isoelectric point and fluorescence with dansyl undecanoic acid suggests that the FABP may not be of the heart type, but is rather more closely related to the liver type. As malignant prostatic tissue produces more PGE2 compared to benign tissue, our data suggest that FABP may help enhancing the synthesis of the prostaglandin in malignant tissue by facilitating arachidonic acid transport.
Trans‐monoenoic and polyunsaturated fatty acids in phospholipids of aVibrio species of bacterium in relation to growth conditions
Authors: Henderson R. J. , Millar R. ‐M. , Sargent J. R. , Jostensen J. ‐P. 
Published: November 2006

AbstractAVibrio species of bacterium known to contain the polyunsaturated fatty acid 20∶5n−3 was grown in both freshwater and seawater media at 5 and 20°C and examined for adaptive changes in lipid composition. Phosphatidylethanolamine (PE) and phosphatidylglycerol (PG), together with a smaller proportion of nonesterified fatty acids (NEFA), comprised almost all the lipid under all growth conditions examined. Temperature had a more pronounced effect than the salinity of the medium on lipid composition. The proportion of PE in total lipid was always higher at 5 than at 20°C. Conversely, the proportion of NEFA was lower at 5 than 20°C whereas that of PG was not altered. The levels of saturated fatty acids in total lipid, PE and PG were all decreased by growth at 5°C. No differences were observed with respect to growth temperature in the levels ofcis 16∶1n−7, the principal monoenoic fatty acid in both PE and PG.Trans 16∶1n−7 was found to comprise 12.8–15.2% of fatty acids in PE and PG of bacteria grown at 5°C but only 4.4–8.5% of phospholipid fatty acids in bacteria cultured at 20°C. Regardless of medium composition, a reduction in growth temperature from 20 to 5°C also caused the proportions of 20∶5n−3 to increase from around 0.8 to 4.4% in PE and from around 4 to 20% in PG. The simultaneous occurrence oftrans 16∶1n−7 and 20∶5n−3 is unique to thisVibrio species of bacterium. The increased proportions of both these fatty acids with decreasing temperature suggest that they have a role in retailoring biomembrane phospholipids during temperature acclimation of the bacterium.
2‐Hydroxyhexadecanoic and 8,9,13‐trihydroxydocosanoic acid accumulation by yeasts treated with fumonisin B1
Authors: Kaneshiro Tsuneo , Vesonder Ronald F. , Peterson Robert E. , Bagby Marvin O. 
Published: November 2006

AbstractFumonisin B1 is a sphingolipid‐like compound that enhances the accumulation of yeast sphingolipids and 2‐hydroxy fatty acids. These lipids occur both as freely extractable and cell bound components in yeast fermentations. Both free and bound 2‐hydroxy fatty acids produced byPichia sydowiorum NRRL Y‐7130 were increased when fumonisin B1 (50 mg/L) was added to the usual growth medium containing yeast extract/malt extract/peptone/glucose. Fumonisin‐treated cultures contained 38 mg/L more 2‐hydroxyhexadecanoic and 15 mg/L more 2‐hydroxyoctadecanoic acids than did untreated cultures. By contrast, fumonisin inhibited the accumulation of free 8,9,13‐trihydroxydocosanoic acid inRhodotorula sp. YB‐2501 cultures, leading to 240 mg/L lower trihydroxy acid production than by untreated cultures.
Mechanism of decreased arachidonic acid in the renal cortex of rats with diabetes mellitus
Authors: Ramsammy Leslie S. , Haynes Brenda , Josepovitz Christine , Kaloyanides George J. 
Published: November 2006

AbstractThe purpose of this study was to investigate the roles of decreased synthesis and increased consumption in the depression of arachidonic acid levels in renal cortex and glomeruli of rats with streptozotocin‐induced diabetes mellitus. In diabetic rats, arachidonic acid was depressed 33.2% in renal cortex, 47.4% in liver and 66.1% in heart compared to values of control rats. Δ6 Desaturase activity was depressed in renal cortex, liver and heart of diabetic rats to 53.3, 55.5 and 63.7%, respectively, of control values. Δ5 Desaturase activity was also depressed 43.7, 55.5 and 47.6% in renal cortex, liver and heart of diabetic rats, respectively. In other rats the activities of five enzymes involved in the synthesis and esterification of arachidonic acid were measured in renal cortex and in isolated glomeruli. Both tissues from diabetic rats showed depressed activities of Δ5 and Δ6 desaturases, increased activities of long‐chain acyl‐CoA synthetase and 1‐acyl‐sn‐glycero‐3‐phosphocholine acyltransferase and no change in the activity of elongase as compared to those in control tissues. Malondialdehyde, an end product of lipid peroxidation, was lower in the renal cortex of diabetic rats than in control rats, whereas β‐oxidation of linoleic acid and arachidonic acid were similar in diabetic and in control rats. Basal and stimulated prostaglandin E2 synthesis were significantly higher in isolated glomeruli from diabetic rats compared to those in control rats. In isolated tubules, prostaglandin E2 synthesis was similarly low in both groups. From these data we conclude that the reduced level of arachidonic acid esterified in lipids of the kidney cortex is caused principally by depressed synthesis of arachidonic acid secondary to decreased activity of Δ5 and Δ6 desaturases. Increased consumption of arachidonic acid to support prostaglandin synthesis may have contributed to the depression of arachidonic acid in glomeruli but not in tubules.
Effect of high fat corn oil, olive oil and fish oil on phospholipid fatty acid composition in male F344 rats
Authors: Rao Chinthalapally V. , Zang Edith , Reddy Bandaru S. 
Published: November 2006

AbstractEpidemiological and laboratory animal model studies have provided evidence that the effect of dietary fat on colon tumorigenesis depends on the amount of fat and its composition. Because of the importance of the composition of dietary fat and of tissue membrane fatty acid composition in tumor promotion, experiments were designed to investigate the relative effects of high fat diets rich in ω3, ω6 and ω9 fatty acids and colon carcinogen on the phospholipid fatty acid composition of liver, colon, small intestine, erythrocytes and blood plasma. At 6 wk of age, groups of animals were fed diets containing 5% corn oil (LFCO), 23.5% corn oil (HFCO), 23.5% olive oil (HFOO), and 20.5% fish oil plus 3% corn oil (HFFO). Two weeks later all the animals except the vehicle‐treated animals received azoxymethanes.c. once weekly for 2 wk at a dose rate of 15 mg/kg body weight. Animals were sacrificed 5 d later and liver, colon, small intestine and erythrocytes and blood plasma were analyzed for phospholipid fatty acids. The results indicate that the phospholipid fatty acid composition of liver, colon and small intestine of HFCO diet fed animals, were not significantly different from those fed the LFCO diet. The levels of palmitoleic acid and linoleic acid were increased in erythrocytes and blood plasma of the animals fed the HFCO diet compared to those fed the LFCO diet. Feeding the HFCO diet significantly increased the oleic acid content and decreased the linoleic acid and arachidonic acid levels in various organs when compared to the HFCO diet. Animals fed the HFFO diet showed a marked increase in eicosapentaenoic acid and docosahexaenoic acid and a decrease in linoleic acid and arachidonic acid levels as compared to those fed the HFCO diet. The results also indicate that carcinogen treatment had only a minimal effect on the phospholipid fatty acid composition.
Effects of dietary proteins on linoleic acid desaturation and membrane fluidity in rat liver microsomes
Authors: Koba Kazunori , Wakamatsu Kosaburo , Obata Keisuke , Sugano Michihiro 
Published: November 2006

AbstractThe effect of dietary protein, casein (CAS) and soybean protein (SOY), on linoleic acid desaturation in liver microsomes was studied in rats. The activity of Δ6 desaturase in total and rough endoplasmic reticula (ER and RER) was significantly higher in the CAS group than in the SOY group. In ER and smooth endoplasmic reticulum, the steady‐state fluorescence anisotropy of 1,6‐diphenyl‐1,3,5‐hexatriene, when incorporated into the membrane, was decreased in the SOY group and accompanied by a reduction in the cholesterol/phospholipid (CHOL/PL) ratio, consistent with an increase in membrane fluidity. In a separate study, the effect of varying dietary proteins, CAS, milk whey protein, egg albumin, SOY, potato protein and wheat gluten, on the relationship between the Δ6 desaturase activity and microsomal membrane fluidity was also examined. The results indicated that the dietary protein‐dependent change in the liver microsomal CHOL/PL ratio affected membrane fluidity, and subsequently the activity of Δ6 desaturase in liver microsomes. However, since dietary protein influenced the Δ6 desaturase activity in RER without influencing membrane fluidity, it is possible that some regulation might have taken place at the level of enzyme synthesis.
Sterols ofChaetoceros andSkeletonema
Authors: Tsitsa‐Tzardis E. , Patterson G. W. , Wikfors G. H. , Gladu P. K. , Harrison D. 
Published: November 2006

AbstractDietary sterol is required by the oyster for growth, and sterol is believed to be obtained primarily from dietary phytoplankton. Seven isolates ofChaetoceros and one ofSkeletonema, which are of potential use as oyster food, were analyzed for sterol composition using gas chromatography, high‐performance liquid chromatography and gas chromatography/mass spectrometry.Skeletonema and five isolates ofChaetoceros contained cholesterol as their major sterol. Two other isolates ofChaetoceros also contained cholesterol, but 24‐methylenecholesterol was the principal sterol. Cholesterol has rarely been reported as the major sterol from phytoplankton. In view of the widespread occurrence ofSkeletonema andChaetoceros in the marine environment, these algae could be an important source of the oyster's cholesterol.
Changes in fatty acid desaturation in hepatic and intestinal tissues induced by intestinal resection
Authors: Vázquez C. M. , Muriana F. J. G. , Ruiz‐Gutierrez V. 
Published: November 2006

AbstractWe have studied the activities of Δ9, Δ6 and Δ5 desaturases in rat liver and jejunum when the entero‐hepatic circulation was interrupted by either 50 or 75% intestinal resection. Desaturase activities in caecal mucosa were also determined in control and operated rats. Distal small bowel resection significantly altered the activities of desaturase enzymes in liver, jejunum and caecum. Thus, the Δ9 desaturase activity was lower in hepatic microsomes from operated animals, and this decrease was not related to the extent by which the intestine was removed. However, a significant increase in both Δ6 and Δ5 desaturases was found in these animals compared to shamoperated rats, the increase in both desaturases being higher after 75% than after 50% intestinal resection. The activities of Δ9 and Δ5 desaturases were significantly increased in jejunal mucosa of resected rats. The activity of Δ6 desaturase was increased only in 50% resected‐animals. An increase in Δ6 desaturase activity was observed in caecal mucosa after resection, together with a decrease in Δ9 desaturase and no change in Δ5 desaturase activities. Enzyme activities were highest in the liver relative to the activity in jejunal and caecal homogenates. In sham rats, the caecal mucosa showed higher Δ9 and Δ6 but lower Δ5 desaturase activities than in jejunal mucosa.
Specific accumulation of docosahexaenoic acid (22∶6n−3) in brain lipids during development of juvenile turbotScophthalmus maximus L.
Authors: Mourente Gabriel , Tocher Douglas R. , Sargent John R. 
Published: November 2006

AbstractThe changes in the lipid class and the fatty acid compositions of total lipids and individual glycerophospholipids which occur in brain during development of juvenile turbot (Scophthalmus maximus L.) were investigated. Fish were sampled during a 10‐week period immediately following weaning from a live feed to a pellet diet. During this period, brain dry weight increased over 6‐fold. The percentages of protein, cholesterol and galactolipids increased in brain during development, presumably reflecting increased membrane maturation and myelination processes. The percentages of docosahexaenoic acid (DHA; 22∶6n−3) were low at the beginning of the study period. However, DHA specifically accumulated in juvenile turbot brain during development. The percentages of DHA increased in total lipid, total diradyl glycerophosphocholine (GPC), total diradyl glycerophosphoethanolamine (GPE), phosphatidylserine (PS) and phosphatidylinositol (PI) reaching 26.1%, 25.8%, 40.8%, 47.1% and 17.9% of the total fatty acids, respectively, by the end of the 10‐week period. The percentages of other n−3 polyunsaturated fatty acids (PUFA) and n−6 PUFA generally decreased during this period, as did that of monoenes; the percentages of saturated fatty acids remained relatively constant. Non‐linear regression analysis showed that the increase in DHA in total lipid, GPC, GPE and PS fitted 1st order rate kinetics (plus offset) allowing maximum values for the percentages of DHA in each lipid class to be estimated.
Metabolic transformation of intracraneally injected [1‐14C]linoleic and [1‐14C]α‐linolenic acids in malnourished developing rats
Authors: De Tomas Maria Elena , Mercuri Osvaldo , Serres Cristina 
Published: November 2006

AbstractThe effect of a low protein diet during pregnancy and lactation on the fatty acid composition of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) from brains of ten‐day‐old rats was studied. The results indicated that partial deprivation of protein during early development was associated with an increase in the fatty acids of the n−9 family in PC. The fatty acids of the linoleic acid series decreased in PE but were not modified in PC. These minor changes did not affect the double bond index values either in PC or in PE. The effect of protein depletion on thein vivo metabolic transformation of intracraneally injected [1‐14C]linoleic and [1‐14C]α‐linolenic acids was also studied. The percentage distribution of the labeled precursors and their derivatives among PC and PE differed from that of mass distribution. These results indicate that the direct uptake of polyunsaturated fatty acids from the blood and/or the low turnover rate of these acids incorporated into PC and PE might be involved in maintaining the fatty acid pattern of these brain lipids.
Effect of dietary fat on rat liver microsomal and mitochondrial/lysosomal dolichol, phospholipid and cholesterol
Authors: Jakobsson‐Borin Åsa , Tollbom Örjan , Dallner Gustav 
Published: November 2006

AbstractThe influence of different fat diets on liver phospholipid, cholesterol and dolichol was studied. Rats were separated into four groups and fed standard laboratory chow (control), a diet containing linolenic acid, a coconut oil diet, or a corn oil‐containing diet. After five weeks, microsomes and mitochondrial/lysosomal fractions were prepared from the liver, and lipid compositions were analyzed. No changes in phospholipid content were observed. In control animals, the fatty acid compositions of phosphatidylcholine and phosphatidylethanolamine in the two subfractions were similar. However, these two phospholipids showed different fatty acid patterns, which were altered independently upon dietary treatment. The dietary treatments resulted, in most cases, in decreased cholesterol and dolichol contents and, especially in microsomes, in a decreased level of esterification of both lipids. The fatty acid compositions of cholesteryl esters in the two subfractions showed significant differences and cholesterol was esterified to a large extent with linolenic acid when this fatty acid was supplied in the diet. The same dietary treatment exerted different effects on the cholesterol localized in the two different intracellular compartments. This difference was most pronounced in rats fed the corn oil‐containing diet; microsomal cholesteryl esters exhibited increased saturation, whereas cholesteryl esters in the mitochondrial/lysosomal fraction displayed decreased saturation. Dolichyl esters in the two cellular compartments had different fatty acyl compositions, with a considerably higher degree of saturation in microsomes. The various diets influenced the nature of the fatty acid moieties present in the isolated fractions and the effects on the two subfractions were opposite. The diet containing linolenic acid decreased the degree of saturation in microsomal dolichyl esters and increased the degree of saturation in the mitochondrial/lysosomal fraction. The results demonstrate that the fatty acid compositions of both dolichyl and cholesteryl esters display organelle specificity. Both the content of these lipids and their fatty acid compositions are greatly influenced by dietary conditions, and the esterification processes at different cellular locations exhibit independent regulation, regardless of the fatty acid content of the diet.
Formation of dityrosine and other fluorescent amino acids by reaction of amino acids with lipid hydroperoxides
Authors: Kikugawa Kiyomi , Kato Tetsuta , Hayasaka Akira 
Published: November 2006

AbstractFormation of fluorescence by the reaction of various amino acids with lipid hydroperoxides,i.e., linoleic acid 13‐monohydroperoxide, methyl linoleate 13‐monohydroperoxide and phosphatidylcholine hydroperoxide, in the presence of methemoglobin was investigated. Two types of fluorescence were produced: fluorescent dityrosine (3,3′‐dityrosine) from tyrosine, and unidentified fluorophores with α‐ and ε‐amino groups of various amino acids. While the former was stable after treatment with borohydride, the latter fluorophores were readily destroyed. The rate of dityrosine formation was rapid, and the yield of dityrosine was dependent on the concentrations of tyrosine and the lipid hydroperoxides. Butylated hydroxytoluene and tocopherol inhibited the formation of dityrosine, but did not affect the formation of fluorophores on the amino groups. Dityrosine appears to be formed by radical reaction of the lipid hydroperoxides, while the other fluorophores seem to be created by nonradical mechanisms.
Changes in lipids of pigeon “milk” in the first week of its secretion
Authors: Shetty Sreerama , Hegde S. N. 
Published: November 2006

AbstractPigeon “milk” (PM) collected from the crop of 1‐ to 5‐day‐old squabs was analyzed to examine whether there were changes in lipid composition during the first week of secretion. The high PM fat content (9–11%) remained fairly constant in the first 5 days of secretion. The mean percentage of neutral lipids, glycolipids and phospholipids was 80, 12 and 8%, respectively. Unlike the content of neutral lipids, glycolipid and phospholipid levels increased significantly between day 1 and day 5 of secretion. Triglycerides, the major neutral lipids, decreased by 24% between day 1 and day 5, while free sterols, monoglycerides and hydrocarbons increased by 8%, 11% and 2.5%, respectively, during the same period; diglycerides and sterol esters, however, remained unchanged. The ratio of saturated to unsaturated fatty acids was 0.27 and it remained unchanged. Medium‐chain (C10, C12 and C14) and oddchain (C15 and C17) fatty acid contents were low. Fatty acids longer than C20 were absent. Palmitic acid, the major saturated fatty acid, increased by 42% from day 1 to day 5, whereas stearic acid decreased by 48% during the same period. Oleic acid, the predominant unsaturated fatty acid, also decreased from 51 to 45% between the first and fifth day of PM secretion. Polyunsaturated acids (18∶2, 18∶3 and 20∶4) accounted for 26% and 30% of the total fatty acids on day 1 and day 5, respectively. Although lipid changes in the crop of squabs prior to collection of samples cannot totally be ruled out, the nature of lipid changes is likely to reflect cellular breakdown that precedes PM secretion by parent pigeons.
Identification of natural diacylglycerols as the 3,5‐dinitrophenylurethanes by chiral phase liquid chromatography with mass spectrometry
Authors: Itabashi Y. , Marai L. , Kuksis A. 
Published: November 2006

AbstractThis study reports a facile identification of the molecular species of enantiomeric diacylglycerols by combining chiral phase high‐performance liquid chromatography with positive chemical ionization mass spectrometry. For this purpose the 3,5‐dinitrophenylurethane (DNPU) derivatives ofsn‐1,2(2,3)‐diacylglycerols are separated on an (R+)‐naphthylethylamine polymer column (25 cm × 0.46 cm ID) using an isocratic solvent system made up of hexane/dichloroethane/acetonitrile (85∶10∶5, by vol) or isooctane/tert‐butyl methyl ether/acetonitrile/isopropanol (80∶10∶5∶5, by vol). About 1% of the column effluent (1 mL/min) was admitted to a quadrupole mass spectrometer (Hewlett‐Packard, Palo Alto, CA)via direct liquid inlet interface, and positive chemical ionization spectra were recorded over the range of 200–900 mass units. The DNPU derivatives of diacylglycerols yield characteristic [M‐DNPU]+ and [RCO+74]+ ions for each diacylglycerol species from which the molecular weight and exact pairing of fatty acids can be unequivocally obtained. The characteristic ions appear to be generated in nearly correct mass proportions as indicated by preliminary quantitative comparisons.
Inhibition of theClostridium perfringens phospholipase C hydrolysis of a thiophosphate analog of lysophosphatidylcholine by micelle‐bound ammonium and sulfonium cations
Authors: Young Paul R. , Snyder William R. , McMahon Rosemary F. 
Published: November 2006

AbstractCetyltrimethylammonium andn‐octadecyldimethylsulfonium bromides inhibit theClostridium perfringens phospholipase C‐catalyzed hydrolysis of 1‐S‐phosphocholine‐2‐O‐hexadecanoyl‐1‐mercapto‐2‐ethanol (1) at pH 7.5, 37°C, μ=0.15 with KCl. Mixed micelles containing 1 and either inhibitor are substrates for the enzyme and the fraction of activity remaining is a monotonic, but nonlinear function of the mole fraction of inhibitor. Simple saturation kinetics are observed as the concentration of 1 is increased in mixed micelles containing a constant mole fraction of inhibitor. Inhibition constants for cetyltrimethylammonium andn‐octadecyldimethylsulfonium bromides are 0.66±0.04 and 0.25±0.02 mM, respectively. The data suggest that the significant inhibition previously observed for soluble alkyldisulfonium salts (K50 for dodecamethylene‐bis(dimethylsulfonium) bromide, 27μM) is dependent upon bifunctional cationic interactions rather than hydrophobic binding.