bluuebunny/crossref_metadata_2025_split huggingface dataset:
Higher levels of plasma cholesterol sulfate in patients with liver cirrhosis and hypercholesterolemia
Authors: Tamasawa Naoki , Tamasawa Atsuko , Takebe Kazuo 
Published: November 2006

AbstractAn analytical method for the determination of cholesterol sulfate (CS) in plasma using gas‐liquid chromatography was developed. We measured plasma CS concentrations in patients with liver cirrhosis and hypercholesterolemia as examples of disorders that involve aberrations in cholesterol metabolism. Patients with liver cirrhosis had plasma CS concentrations that were significantly higher than those of control subjects (444.6±51.7vs. 253.0±24.6 μg/dL, mean ±SE). The levels of other lipids were lower in cirrhotics, although the differences were not significant. There was no correlation between the levels of CS and sulfated bile acids in cirrhotic patients. CS levels in plasma were also higher in subjects with hypercholesterolemia (413.7±44.5 μg/gL) however, the ratio of CS to total cholesterol (TC) clearly differed between cirrhotics and hypercholesterolemic subjects (1.44±0.11×10−3,vs. 3.31 ±0.63×10−3;P<0.05). Both in subjects with hypercholesterolemia and in healthy controls, the CS/TC ratio was similar and CS accounted for roughly 0.14% of the TC concentration.
γ‐linolenic acid inAnemone spp. seed lipids
Authors: Tsevegsüren Nansadyn , Aitzetmüller Kurt 
Published: November 2006

Abstractγ‐Linolenic acid containing oils have been found in seed lipids of a number of plants, but are restricted to certain genera and families,e.g., the Boraginaceae. Some of these oils have found considerable interest for pharmaceutical and dietary use,e.g., borage oil and evening primrose oil in treatment of essential fatty acid and Δ6 desaturase deficiency. Our investigation of the seed lipids of certain Mongolian and other Ranunculaceae has now shown the presnce of unusual fatty acids, including considerable amounts (up to 20%) ofγ‐linolenic acid in certain species ofAnemone, whereas this acid was found to be absent in other species ofAnemone. A number of other unusual fatty acids are present inA. rivularis but have not yet been identified. The significance of the presence ofγ‐linolenic acid, a Δ6 acid, is discussed in relation to δ5 fatty acids that had been reported to occur in the same plant family.
Synthesis of ethyl arachidonate‐19,19,20,20‐d4 and ethyl dihomo‐γ‐linolenate‐19,19,20,20‐d4
Authors: Luthria Devanand L. , Sprecher Howard 
Published: November 2006

AbstractEthyl 5,8,11,14‐eicosatetraenoate‐19,19,20,20‐d4 and ethyl 8,11,14‐eicosatrienoate‐19,19,20,20‐d4 were synthesized by Grignard coupling of the methanesulfonyl ester of 2,5‐undecadiyn‐1‐ol‐10,10,11,11‐d4 with 5,8‐nonadiynoic acid and 8‐nonynoic acid, respectively. The coupled products upon Lindlar reduction, followed by the preparation of their ethyl esters, yielded deuteriated ethyl arachidonate and ethyl dihomo‐γ‐linolenate, which were completely characterized by13C and1H nuclear magnetic resonance and mass spectral analysis.
Low‐fat diets do not lower plasma cholesterol levels in healthy men compared to high‐fat diets with similar fatty acid composition at constant caloric intake
Authors: Nelson Gary J. , Schmidt Perla C. , Kelley Darshan S. 
Published: November 2006

AbstractIn most studies reporting the effects of high‐fat (HF) and low‐fat (LF) diets on human plasma fatty acids (FA) and lipoprotein levels, the design involved adding to the diet an oil that had an FA composition (FAC) very different from the FAC of the control diet. Thus, it is difficult to determine if simply reducing the fat content of the diet without changing the dietary FAC changes the tissue FAC or alters plasma lipid levels. In this study, we fed diets that contained either 22 or 39% of calories from fat, but had no differences in their FAC, for 50 d to a group (n=11) of healthy men (20–35 y). Thus, the polyunsaturated/saturated ratios (1.0) of the diets were identical as were the n−3/n−6 ratio and the monounsaturated‐to‐total fat ratios. The diets contained (wt% of total fat) approximately 28% saturated FA, 33% monounsaturatedcis‐FA, 6% monounsaturatedtrans‐FA, 22% n−6 polyunsaturated FA, and 7% n−3 polyunsaturated FA, and 4% other minor FA. The diets consisted of natural foods and were formulated to contain 16 en% protein, either 45 or 62 en% carbohydrate (CHO) and at least the recommended dailyallowance for all micronutrients. Both diets contained 360 mg of cholesterol per day. All subjects were given the HF diet for 20 d, and then six were placed on the LF and the other five remained on the HF diet for 50 d. The two groups were crossedover for the remaining 50 d of the study. The subjects' baseline total cholesterol level was 173 mg/dl, after 50 d on the HF diet it was 177 mg/dl and after 50 d on the LF diet, 173 mg/dl. The differences were not significant, and there were no significant changes in either the LDL or HDL cholesterol levels with either diet. Triglyceride levels, and consequently very low density lipoprotein levels, rose significantly on the LF, higher CHO diet compared to the levels found in the subjects on the HF diet (91.5 and 66.4 mg/dl respectively,P<0.002). The linoleic acid content of the plasma, platelets, and red blood cells was significantly (P<0.05) reduced in the LF diet compared to HF diet, without any obvious physiological effects. Hence, many earlier observations indicating reductions in plasma lipid levels when people are on LF diets may be due to changes in the FAC of the diet, not the reduction in fat calories.
Changes in linoleic acid metabolism and membrane fatty acids of LLC‐PK cells in culture induced by 5α‐cholestane‐3β, 5, 6β‐triol
Authors: Mahfouz M. , Smith T. , Kummerow F. A. 
Published: November 2006

AbstractThe aim of this study was to investigate the effect of the oxysterol 5α‐cholestane‐3β, 5, 6β‐triol (triol) on the metabolism of linoleic acid (18∶2n−6) to arachidonic acid (20∶4n−6) and on the cell membrane fatty acid composition. Porcine kidney cells were incubated in medium with or without 10 μg/mL of triol for 24 h, then incubated for 1, 6, or 12 h in a medium which contained 50 μM of either [14C]linoleic acid or unlabeled linoleic acid. The cellular uptake of [14C] linoleic acid was significantly higher in the triol‐treated cells than in control cells. After 1‐ and 6‐h incubations despite the increase of [14C]linoleic acid pool size in the triol‐treated cells, neither total n−6 polyunsaturated fatty acids (PUFA) metabolites nor arachidonic acid were increased in the triol‐treated cells as compared to the control cells, but trienoic acids accumulated to a greater extent in the triol‐treated cells. Therefore, the ratios of n−6 PUFA metabolites vs. pool size of linoleic acid and of tetraenoic acids vs. dienoic acids were significantly decreased in triol‐treated cells as compared to the control cells. The cellular fatty acid composition also showed that linoleic acid percentage was significantly increased while arachidonic acid percentage was significantly decreased in the triol‐treated cells, and that the accumulation of trienoic acids (18∶3n−6+20∶3n−6) observed from the [14C]linoleic acid experiment was due solely to increased 20∶3n−6 content. This latter finding indicates that a decrease of elongase activity by triol is unlikely. Our results also showed that the triol‐treated cells had a lower level of free cholesterol but higher levels of phospholipid and triol in their membranes, suggesting that triol displaced free cholesterol from the cell membrane.
Enzymatic hydrolysis of long‐chainN‐heterocyclic fatty esters
Authors: Jie Marcel S. F. Lie Ken , Syed‐Rahmatullah M. S. K. 
Published: November 2006

AbstractIncubation of a 1‐pyrroline ester [viz. methyl 8‐(5‐hexyl‐1‐pyrroline‐2‐yl)octanoate,1] with bakers' yeast (Saccharomyces cerevisiae) gave the corresponding free fatty acid (1a, 52%). The C=N bond of the 1‐pyrroline was not reduced by the yeast. Complete hydrolysis of compound1 was successful using lipase ofCandida cylindracea (CCL) or Lipolase (Rhizomucor miehei) under stirred or ultrasound condition. Fatty esters containing a pyrrolidine [viz. methyl 8‐(cis/trans‐5‐hexyl‐pyrrolidine‐2‐) octanoate,2] orN‐methyl pyrrolidine [viz. methyl 8‐(cis‐5‐hexyl‐N‐methyl‐pyrrolidine‐2‐)octanoate,3] system in the alkyl chain were not hydrolyzed by either CCL or Lipolase, unless conducted in an ultrasonic bath. The hydrolytic activities of the enzymes appeared to be strongly affected by the stereochemistry of theN‐heterocyclic ring system. Chemical hydrolysis of compounds1–3 gave the corresponding fatty acidN‐HCl salts.
Chemiluminescence detection of mono‐, bis‐, and tris‐hydroperoxy triacylglycerols present in vegetable oils
Authors: Miyazawa Teruo , Kunika Hikoichiro , Fujimoto Kenshiro , Endo Yasushi , Kaneda Takashi 
Published: November 2006

AbstractA reliable method was needed to analyze molecular species of oxidized vegetable oils. In order to accomplish this goal, mono‐, bis‐, and tris‐hydroperoxides (Mono‐OOH, Bis‐OOH, and Tris‐OOH, respectively) of triacylglycerols formed during autoxidation and photosensitized oxidation of oils were determined by reversed‐phase high‐performance liquid chromatography in combination with chemiluminescence detection (CL‐HPLC). Mono‐OOH was the major species (96% of total hydroperoxides) in trioleoylglycerol [peroxide value (PV) 0.16 meq/kg], and Bis‐OOH and Tris‐OOH showed prolonged accumulation with photooxidation. This profile was confirmed in photooxidation of trilinoleoylglycerol and trilinolenoylglycerol. Soybean oil (PV 6 meq/kg) contained Mono‐OOH oleoyl‐linoleoyl‐linoleoylglycerol as the main peroxidic molecular species (50% of total hydroperoxides). Mono‐OOH trilinoleoylglycerol was the principal species (61% of total hydroperoxides) in safflower oil (PV 5 meq/kg), and Mono‐OOH oleoyl‐oleoyl‐linoleoylglycerol was the representative species (66% of total hydroperoxides) in olive oil (PV 3 meq/kg). The CL‐HPLC method, which is specific for the detection of hydroperoxides, should prove useful in studies of triacylglycerol oxidation in foods and vegetable oils.
Biodiscrimination of α‐tocopherol stereoisomers during intestinal absorption
Authors: Kiyose Chikako , Muramatsu Riho , Fujiyama‐Fujiwara Yoko , Ueda Tadahiko , Igarashi Osamu 
Published: November 2006

AbstractSynthetic α‐tocopherol (α‐Toc) contains equal amounts of eight different stereoisomers, and the four stereoisomers with the 2R configuration are generally more active than their correspoding 2S‐isomers. We investigated the biodiscrimination of α‐Toc stereoisomers during intestinal absorptionin situ andin vitro. Intestinal absorption of α‐Toc stereoisomers was examinedin situ in vitamin E‐deficient rats with cannulated thoracic ducts. We found that the ratios of α‐Toc stereoisomers in lymph of the all‐rac‐α‐Toc group were the same as the administered α‐Toc stereoisomers, and 2R‐isomers occupied approximately 50% of absorbed α‐Toc. The uptake of α‐Toc stereoisomers also was measured using Caco‐2 cells cultured on filter membranes. The concentration ofRRR‐α‐Toc in Caco‐2 cells was not significnatly different from that ofSRR‐α‐Toc. Therefore, the discrimination of α‐Toc stereoisomers does not occur during absorption in small intestine, suggesting the liver as a source for the biodiscrimination.
Dietary menhaden oil enhances mitomycin C antitumor activity toward human mammary carcinoma MX‐1
Authors: Shao Yu , Pardini Lani , Pardini Ronald S. 
Published: November 2006

AbstractIn the present study, we investigated the effects of high levels of dietary fish oil on the growth of MX‐1 human mammary carcinoma and its response to mitomycin C (MC) treatment in athymic mice. We found that high levels of dietary fish oil (20% menhaden oil+5% corn oil, w/w) compared to a control diet (5% corn oil, w/w) not only lowered the tumor growth rate, but also increased the tumor response to MC treatment. We also found that high levels of dietary fish oil significantly increased the activities of tumor xanthine oxidase and DT‐diaphorase, which are proposed to be involved in the bioreductive activation of MC. Since menhaden oil is highly unsaturated, its intake caused a significant increase in the degree of fatty acid unsaturation in tumor membrane phospholipids. This alteration in tumor membrane phospholipids made the tumor more susceptible to oxidative stress, as indicated by the increased levels of both endogenous lipid peroxidation and protein oxidation after feeding the host animals the menhaden oil diet. In addition, the tumor antioxidant enzyme activities, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPOx), and glutathione S‐transferase peroxidase (GSTPx), were all significantly enhanced by feeding a diet high in fish oil. MC treatment caused further increases in tumor lipid peroxidation and protein oxidation, as well as in the activities of CAT, SOD, GPOx, and GSTPx, suggesting that MC causes oxidative stress in this tumor model which is exacerbated by feeding a diet high in menhaden oil. Thus, feeding a diet rich in menhaden oil decreased the growth of human mammary carcinoma MX‐1, increased its responsiveness to MC, and increased its susceptibility to endogenous and MC‐induced oxidative stress, and increased the tumor activities of two enzymes proposed to be involved in the bioactivation of MC, that is, DT‐diaphorase and xanthine oxidase. These findings support a role of these two enzymes in the bioactivating of MC and indicate that the type of dietary fat may be important in tumor response to therapy.
Phospholipid profiling of sediments using phosphorus‐31 nuclear magnetic resonance
Authors: Bardygula‐Nonn Lidia G. , Kaster Jerry L. , Glonek Thomas 
Published: November 2006

AbstractA phosphorus‐31 nuclear magnetic resonance method has been developed for the determination of aquatic sediment phospholipid profiles that may be generally applied to all soils and deposits containing viable cellular material. A method of scrubbing chloroform/methanol extracts with potassium acid phosphate overcomes adverse signal broadening from the mineral component, permitting eleven sediment phospholipids to be determined at the quantitative level.
Inhibition of cholesterol synthesis and hepatic 3‐hydroxy‐3‐methylglutaryl‐CoA reductase in rats by simvastatin and pravastatin
Authors: Del Puppoo M. , Rauli S. , Kienle M. Galli 
Published: November 2006

AbstractIn this communication we attempt to provide one possible explanation for the observed differences regarding kinetics and distribution between simvastatin and pravastatin. Rats treated with simvastatin or pravastatin exhibited a reduction in the incorporation of [2‐14C]acetate into liver cholesterol and displayed lower plasma mevalonate levels as compared to control animals. Moreover, both the total and dephosphorylated 3‐hydroxy‐3‐methylglutaryl‐CoA (HMG‐CoA) reductase (EC 1.1.1.34) activities, particularly 1 h after treatment, were greatly reduced in liver microsomes obtained from simvastatin‐treated as compared to control rats. During the same time frame, these parameters were actually elevated with pravastatin treatment. It is known that HMG‐CoA reductase synthesis and activity increase following their competitive inhibition. Our results suggest that pravastatin, at 1 h following treatment, was no longer bound to the enzyme; however, it had entered the liver because its inhibitory effect on cholesterol synthesis was manifest at early times after administration. These data provide a plausible rationale for the earlier observation that activity of simvastatin persists longer in plasma than does that of pravastatin.
Leukotriene B4 stimulation of an early elevation of phosphatidic acid mass in human neutrophils
Authors: Tou Jen‐sie , Dola Thao 
Published: November 2006

AbstractThe signal transduction pathway of leukotriene B4 involves phospholipase D activation in cytochalsin B‐primed neutrophils, but leukotriene B4 stimulation of increased phosphatidic acid mass in neutrophils has not been demonstrated. Employing the NIH Image program, we have examined the effect of leukotriene B4 on phosphatidic acid mass in human neutrophils incubated with or without cytochalasin B. Our results show that 0.15 μM leukotriene B4 without cytochalasin B was capable of increasing phosphatidic acid mass in neutrophils by 2‐fold after 5 s, 2.5‐fold after 1 min, and 2‐fold after 5 min incubation. Leukotriene B3, leukotriene B4, and leukotriene B5 were equipotent stimuli for phosphatidic acid mass elevation. Leukotriene B4 induced phosphatidylethanol formation at the expense of phosphatidic acid in cells preincubated with 0.25–1% ethanol, indicating phospholipase D activation. Cytochalasin B enhanced leukotriene B4 stimulation of phosphatidic acid mass elevation and phosphatidylethanol formation. There were no measurable changes in 1,2‐diglyceride mass after 5 s, but a 1.7‐fold increase occurred after 1 min and declined thereafter. Leukotriene B4 stimulation of [3H]glycerol incorporation into phosphatidic acid, diglyceride and phosphatidylinositol was detectable after a 1‐min incubation, suggesting increasedde novo synthesis of these lipids. These results suggest that leukotriene B4 stimulation of phospholipase D activity contributes to part of the early increased phosphatidic acid mass and that combined actions of stimulated phospholipases C and D, andde novo phosphatidic acid synthesis contribute to the total increased phosphatidic acid mass.
The effect of two synthetic phospholipids on cell proliferation and phosphatidylcholine biosynthesis in Madin‐Darby canine kidney cells
Authors: Wieder Thomas , Haase Anne , Geilen Christoph C. , Orfanos Constantin E. 
Published: November 2006

AbstractThe concentration‐dependent effects of two different synthetic phospholipids on cell proliferation and phosphatidylcholine biosynthesis were compared in Madin‐Darby canine kidney (MDCK) cells. The alkyllysophospholipid 1‐O‐octadecyl‐2‐O‐methyl‐sn‐glycero‐3‐phosphocholine and the alkylphosphocholine, hexadecylphosphocholine, inhibited cell proliferation with half‐inhibitory concentrations (IC50) of 75 and 135 μmol/L, respectively. The agents also inhibited phosphatidylcholine biosynthesis in confluent and proliferating MDCK cells. The IC50 of 1‐O‐octadecyl‐2‐O‐methyl‐sn‐glycero‐3‐phosphocholine was 40 μmol/L in confluent cells and 20 μmol/L in proliferating cells, whereas the IC50 of hexadecylphosphocholine was higher in both experimental systems (67 μmol/L in confluent cells and 40 μmol/L in proliferating cells). Further experiments revealed that the effect of both agents on phosphatidylcholine biosynthesis was reversible and that the inhibition was mediated by translocation of the rate‐limiting enzyme of this pathway, CTP: phosphocholine cytidylyltransferase (EC 2.7.7.15), from membranes to the cytosol, where it is inactive. The present findings suggest that the inhibition of phosphatidylcholine biosynthesis by both synthetic phospholipids might be related, in part, to their antiproliferative effects.
Oxidized cholesterol modulates age‐related change in lipid metabolism in rats
Authors: Osada Kyoichi , Kodama Takehiro , Noda Satoshi , Yamada Koji , Sugano Michihiro 
Published: November 2006

AbstractFor three weeks, male Sprague‐Dawley rats at either four weeks (young) or eight months (adult) of age were pairfed one of the purified diets free of or containing either 0.2% of oxidized cholesterol mixture (cholesterol oxidation products) or 0.2% of cholesterol. Although the food intake was similar, dietary oxidized cholesterol lowered body weight gain in young rats, but did not increase relative liver weight, in contrast to the enlargement seen with dietary cholesterol. Oxidized cholesterol, compared to cholesterol, tended to reduce the activity of hepatic 3‐hydroxy‐3‐methylglutaryl CoA reductase and cholesterol 7α‐hydroxylase, particularly the latter in aged rats, and prevented the rise in the concentration of liver cholesterol at both ages. It also tended to increase the activity of hepatic δ6 desaturase, particularly in young rats. Moreover, oxidized cholesterol in relation to cholesterol influenced liver and serum lipid concentrations in different ways, and increased lipid peroxidation at both ages. The ratio of splenic CD4+/CD8+ T‐lymphocytes increased with age, but the influence of cholesterol and oxidized cholesterol was comparable. Thus, oxidized cholesterol may specifically disturb growth and age‐related changes in the lipid metabolism in rats.
Evidence that dietary arachidonic acid increases circulating triglycerides
Authors: Whelan Jay , Surette Marc E. , Li‐Stiles Bangyan , Bailey James W. 
Published: November 2006

AbstractMale Syrian hamsters and male CD‐1 mice were fed diets supplemented with ethyl esters of oleic, linoleic, arachidonic, and eicosapentaenoic acids (1.1–1.5%, w/w) for 3–4 wk. Plasma and serum triglycerides were significantly higher in the arachidonic acid‐supplemented animals compared to those in the other supplementation groups. Changes in serum insulin and glucose levels did not appear to be related to the changes in circulating triglycerides observed in the arachidonic acid‐supplemented group. These data indicate that dietary arachidonic acid elevates circulating triglyceride levels compared to other unsaturated fatty acids in hamsters and mice by unknown mechanisms.
Dietary fish oils and long‐term malaria protection in mice
Authors: Fevang Per , Sääv Hjalmar , Høstmark Arne T. 
Published: November 2006

AbstractPrevious studies indicate a suppressive influence of fish oils on rodent malaria. The present work was carried out to study (i) the dose‐effect relation between dietary fish oils and lethality of primary malaria infection in mice; (iii) the modifying influence of vitamin E; and (iii) the effect of previous fish oil feeding on parasitemia and lethality of a rechallenge infection. For two or four weeks, groups of weanling male mice were fed a standard laboratory diet or one of eight purified diets containing various amounts of fish oil (providing 6–21% of energy). The diets were prepared with and without vitamin E. After the two‐or four‐week feeding period, the mice were injected intraperitoneally withPlasmodium yoelii yoelii‐infected erythrocytes. Six months after the primary infection (four months after discontinuing fish oil feeding), the surviving mice were again injected intraperitoneally with parasitized red blood cells (or even better—erythrocytes, erythrocytes are used elsewhere). Primary malaria infection was lethal in mice fed standard diet alone or with fish oil and vitamin E added. In contrast, feeding a fish oil‐based diet without vitamin E improved survival to at least 70% if the mice had been fed these diets for four weeks. Protection against malaria did not seem to be related to the fish oil dose used. Regardless of the previous fish oil dose, all the mice surviving the primary infection survived the rechallenge infection with low parasitaemias. The results suggest that the prooxidant nature of highly unsaturated fatty acids in fish oils may beneficially influence malaria infection, and may also increase the resistance against reinfection for some time after discontinuing fish oil intake.