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PubMed1999

Age-related accumulation of free polyunsaturated fatty acids in human retina.

The present study reports composition of free (nonesterified) as well as total (sum of free and esterified) fatty acids (FAs) in human retina (n = 13). For free fatty acid (FFA) analysis, retina tissue was homogenized, total lipids were partitioned with ethyl acetate and subsequently applied onto a aminopropyl (NH2) cartridge to isolate FFAs from the bulk of other lipids. FFAs were converted to methyl ester derivatives and analysed by gas chromatography using flame ionization detector. Analysis of FFAs revealed that the mean percentage composition of the major components including palmitic acid (PA), stearic acid (SA), oleic acid (OA), arachidonic acid (AA) and docosahexaenoic acid (DHA) were 17.2, 36.7, 15.6, 8.8 and 14.2%, respectively. There were significant correlations between age of the donors' and the content of both free AA and DHA (rPearson = 0.69, p = 0.005, and rPearson = 0.64, p = 0.009). The mean percentage of total PA, SA, OA, AA and DHA were 22.6, 23.2, 17.7, 11.4 and 21.9%, respectively. There was no association between age and any of the major FAs. The present study provides the first evidence for the presence of FFAs in the human retina as well as an age-related accumulation of polyunsaturated fatty acids (PUFAs). The latter finding suggests an alteration in the metabolism of retinal PUFAs which can be due to an increase of oxidative stress and/or decrease of antioxidant defences during ageing.

Adolescent↗
PubMed1995

Influence of dietary supplementation with fish on plasma fatty acid composition in coronary heart disease patients.

The effects of dietary supplementation with fish on plasma fatty acid levels were studied in 20 coronary heart disease patients who had suffered acute myocardial infarction. The study was divided into three periods: hospital admission, after 8 weeks on a heart-healthy diet designed for patients with ischemic heart disease, and after 4 weeks on an n-3 fatty acid-supplemented diet in which red meat was replaced with lean and fatty fish. At the end of each period, the subjects responded to a 48-hour recall questionnaire, so that we could assess their compliance with the diet, and blood samples were collected for the determination of plasma fatty acids. Stearic fatty acid was significantly decreased after the fish diet. n-7 and n-9 fatty acids showed no significant changes throughout the study. At the end of the 4-week period when the fish diet was consumed, linoleic acid and its long-chain derivative docosapentaenoic acid (22:5 n-6) were significantly increased. The most notable changes in n-3 series fatty acids at the end of the third period were the significant decrease in linolenic acid and the significant increase in its long-chain derivatives eicosapentaenoic (20:5 n-3) and docosahexaneoic acid (22:6 n-3). These changes in plasma fatty acid levels may have beneficial effects on coronary heart disease.

Adult↗
PubMed1981

Suppression of IgE antibody response by the fatty acid-modified antigen.

Ovalbumin (OA) of hens was chemically coupled with fatty acids (lauric acid, myristic acid, palmitic acid and stearic acid). These hydrophobically modified antigens were unable to react with mouse antiserum against native OA and were incapable of eliciting primary and secondary anti-OA antibody responses in BALB/c mice. Preadministration of these modified antigens, especially of palmitoyl OA (OA-pal), suppressed both primary and secondary anti-OA IgE antibody responses without affecting IgG antibody production. Administration of OA-pal after the primary immunization resulted in a rapid decrease of the ongoing anti-OA IgE antibody production and inhibited the anamnestic anti-OA IgE antibody response upon subsequent immunization with OA. The passive transfer of spleen cells from OA-pal-treated animals with OA-primed spleen cells suppressed the adoptive secondary anti-OA IgE antibody response in irradiated recipients. The suppressive effect was abrogated by treatment with an anti-T-cell antiserum indicating that suppressor T cells were primed by administration of hydrophobically modified antigens.

Animals↗
PubMed1998

Unsaturated fatty acids increase plasminogen activator inhibitor-1 expression in endothelial cells.

In vivo studies have demonstrated a strong positive correlation between plasma very low density lipoprotein (VLDL) triglyceride and plasma plasminogen activator inhibitor-1 (PAI-1) activity levels. Furthermore, VLDL has been shown to induce PAI-1 secretion from cultured endothelial cells. In contrast, no or variable effects on PAI-1 secretion have been reported for native low density lipoprotein. It could be speculated that fatty acids derived from VLDL triglycerides are the actual mediators, resulting in an enhanced secretion of PAI-1. In the present study, we have analyzed the effects of both saturated and unsaturated fatty acids on PAI-1 expression and secretion by endothelial cells. Addition of 0 to 50 micromol/L of either palmitic acid or stearic acid had no effect on PAI-1 secretion from human umbilical vein endothelial cells or EA. hy926 cells. In contrast, addition of oleic acid, linoleic acid, linolenic acid, and eicosapentaenoic acid resulted in a significant increase in PAI-1 secretion from both cell types. Northern blot analysis of PAI-1 mRNA levels was in agreement with these findings. Transfection experiments demonstrated that addition of linolenic acid and eicosapentaenoic acid significantly increased PAI-1 transcription. The fatty acid response region was localized to a previously described VLDL-inducible region of the PAI-1 promoter. Electromobility shift assays demonstrated that unsaturated fatty acids induced the same complex as did VLDL, whereas saturated fatty acids had no effect. Furthermore, it was demonstrated that the activation procedure did not involve fatty acid oxidation to any significant extent. In conclusion, the present study demonstrates that unsaturated fatty acids increase PAI-1 transcription and secretion by endothelial cells in vitro. The effect appears to be mediated by a previously described VLDL-inducible transcription factor.

Cells, Cultured↗
PubMed1990

Phenytoin affects metabolism of free fatty acids and nucleotides in rat cerebral ischemia.

We investigated the effects of phenytoin on the rate of enzymatic release of free fatty acids and on the levels of energy metabolites and nucleoside phosphates in ischemic brain. Phenytoin (10 mg/kg i.v.) was administered 30 minutes before the onset of ischemia induced in 30 male Wistar rats by occluding the basilar and both common carotid arteries. The rats' brains were frozen in situ after 0, 5, or 30 minutes of ischemia or 10, 30, or 60 minutes of recirculation following 30 minutes of ischemia (n = 5 at each time). Nucleoside triphosphate levels were higher in the phenytoin-treated rats than in corresponding untreated rats at each time during and after ischemia. Phenytoin significantly attenuated the accumulation of lactate and free fatty acids (arachidonic acid and stearic acid) during ischemia and accelerated their recovery during recirculation. These results suggest that phenytoin has favorable protective effects on ischemic brain and that phenytoin may inhibit calcium-mediated phenomena, especially the inositol cycle, in cerebral ischemia.

Animals↗
PubMed2002

The effects of acyl chain length on the micelle properties of poly(ethylene oxide)-block-poly(N-hexyl-L-aspartamide)-acyl conjugates.

Derivatives of poly(ethylene oxide)-block-poly(beta-benzyl-aspartate), 12:25 have been prepared via aminolysis of the benzyl protecting group with 6-amino-1-hexanol, followed by subsequent acylation with acetic anhydride, hexanoic acid, lauric acid, or stearic acid. A series of amphiphilic diblock copolymers based on poly(ethylene oxide)-block-poly(N-hexyl-aspartamide)acyl conjugates with various acyl chain lengths have been prepared. The extent of esterification was determined by 1H-NMR. Aqueous micelle solutions were prepared by a dialysis method and the polymer series was characterized as a function of the acyl chain length. Transmission electron microscopy and dynamic light scattering revealed micelle-like structures of nanoscopic dimensions (< 100 nm). Environmentally sensitive fluorescent probes were loaded into the micelles in order to study the properties of the hydrophobic microdomain and to determine the critical micelle concentration (CMC). Steady-state fluorescence measurements indicated that the relative apparent core viscosity and polarity are modulated by the relative length of the attached acyl chains, as is the CMC. Increasing the acyl chain length results in a decreased CMC and a more viscous and less polar core region. Carefully chosen chemical moieties can be introduced in order to influence the properties of the poly(L-Asp) blocks of the micelles. As a result, the micellar properties can be altered via chemical modification in order to impact several key properties relevant to drug delivery.

Chemistry, Pharmaceutical↗
PubMed2004

Triglyceride levels are ethnic-specifically associated with an index of stearoyl-CoA desaturase activity and n-3 PUFA levels in Asians.

Accumulated evidence suggests that hypertriglyceridemia (HTG) is independently associated with an increased incidence of cardiovascular disease. The hypotriglyceridemic effects of n-3 PUFAs have been confirmed in Caucasians, but the effect in Asians is less clear. Recent evidence indicates that stearoyl-CoA desaturase (SCD) activity induced with high-carbohydrate diets increases plasma triglyceride levels. We investigated the relationship between triglyceride levels and the ratio of plasma oleic acid to stearic acid (the 18:1/18:0 ratio), a plasma marker of SCD activity, and n-3 PUFAs in 411 Japanese, 418 Korean, and 251 Mongolian adults. The Japanese and Koreans had higher values for triglyceride than their Mongolian counterparts, despite lower body mass index values for the Japanese and Koreans. The Japanese and Koreans ate fish more frequently and had remarkably higher values for n-3 PUFAs than did the Mongolians. Multiple regression analysis showed that triglyceride levels had a great magnitude of correlation with the increases in 18:1/18:0 ratio for the Japanese and Mongolians, and n-3 PUFAs remained significant for the Mongolians. HTG is ethnicity-specifically associated with an increase in the 18:1/18:0 ratio and a decrease in n-3 PUFA in plasma for Japanese, Koreans, and Mongolians.

Adult↗
PubMed2005

Apoptosis inducing activity of viscin, a lipophilic extract from Viscum album L.

Detection of antiproliferative activity and bioactivity-guided fractionation of viscin, a lipophilic extract from Viscum album L., led to the isolation of betulinic acid, oleanolic acid and ursolic acid as active components. Viscin, betulinic acid, oleanolic acid and ursolic acid inhibited growth and induced apoptotic cell death in Molt4, K562 and U937 leukaemia cells. The growth inhibitory effect of viscin was more pronounced in Molt4 and U937 cells (IC50 (concentration that inhibited cell proliferation by 50%): 118 +/- 24 and 138 +/- 24 microg mL(-1)) than in K562 cells (IC50: 252 +/- 37 microg mL(-1)). Oleanolic acid was the least effective in all cell lines (7.5-45.5% inhibition at 10 microg mL(-1)) and ursolic acid the most active in Molt4 and U937 cells (81.8 and 97.8% inhibition, respectively, at 5 microg mL(-1)). A dose-dependent loss of membrane phospholipid asymmetry associated with apoptosis was induced in all cell lines as shown in flow cytometry by the externalization of phosphatidylserine and morphological changes in cell size and granularity. There were differences in individual cell lines' response towards the apoptosis-inducing effect of viscin, betulinic acid, oleanolic acid and ursolic acid. The triterpenoids beta-amyrin, beta-amyrinacetate, lupeol, lupeolacetate, beta-sitosterol and stigmasterol, and the fatty acids oleic acid, linoleic acid, palmitic acid and stearic acid were also present in the lipophilic extract.

Antineoplastic Agents, Phytogenic↗
PubMed1994

Effect of fatty acid on the accumulation of thiamine disulfide in rat skin.

The effect of long chain fatty acid (FA) and its analogs on the accumulation of thiamine disulfide (TDS) in rat skin using propylene glycol as a vehicle was studied in vitro. Lauric acid (12:0) increased the accumulation of TDS in skin, while myristic acid and stearic acid caused a slight decrease in accumulation. Lauryl alcohol and lauric acid methyl ester did not change the accumulation of TDS in the skin. The ratio of the amount of TDS accumulated in skin to the solubility of TDS in the vehicle increased dependent on the concentration of 12:0 added in the vehicle. It was suggested that the increase in the permeability coefficient of TDS by 12:0 results from the enhanced transport of TDS from the vehicle to skin.

Animals↗
PubMed2005

Non-esterified fatty acids in follicular fluid of dairy cows and their effect on developmental capacity of bovine oocytes in vitro.

In this study concentration and composition of non-esterified fatty acids (NEFA) in follicular fluid (FF) of high-yielding dairy cows were determined during the period of negative energy balance (NEB) early post partum. NEFA were then added during in vitro maturation at concentrations measured previously in FF to evaluate their effect on the oocyte's developmental competence. At 16 and 44 days post partum, FF of the dominant follicle and blood were collected from nine high-yielding dairy cows. Samples were analysed for NEFA concentration and composition. NEFA concentrations in FF (0.2-0.6 mmol/l) during NEB remained +/- 40% lower compared with serum (0.4-1.2 mmol/l). The NEFA composition differed significantly between serum and FF with oleic acid (OA), palmitic acid (PA) and stearic acid (SA) being the predominant fatty acids in FF. Based on these results, 5115 oocytes were matured for 24 h in serum-free media with or without (negative control) the addition of 0.200 mmol/l OA, 0.133 mmol/l PA or 0.067 mmol/l SA dissolved in ethanol or ethanol alone (positive control). Matured oocytes were fertilized and cultured for 7 days in SOF medium. Addition of PA or SA during oocyte maturation had negative effects on maturation, fertilization and cleavage rate and blastocyst yield. More (late) apoptotic cumulus cells were observed in cumulus-oocyte complexes matured in the presence of SA or PA. Ethanol or OA had no effect. These in vitro results suggest that NEB may hamper fertility of high-yielding dairy cows through increased NEFA concentrations in FF affecting oocyte quality.

Animals↗
PubMed2001

Identification of fatty acid molecules in a Fasciola hepatica immunoprophylactic fatty acid-binding protein.

Fasciola hepatica adult flukes have a native protein complex denoted nFh12 and consisting of fatty acid binding proteins that comprise at least 8 isoforms. It is a potent immunogen because in several animal hosts it induces an early antibody response to F. hepatica infection. It is also a potent cross-protective immunogen because it induces a protective immune response in mice to challenge infection with Schistosoma mansoni cercariae. The gene encoding this protein has been cloned and sequenced. It produces a polypeptide of 132 amino acids with a predicted molecular mass of 14.7 kDa and is denoted rFh15. It also has a significant homology to a 14-kDa S. mansoni fatty acid binding protein (Sm14). In the present study, nFh12 was delipidated with charcoal treatment and then studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Additionally, a lipid analysis of nFh12 was undertaken using gas chromatography-mass spectrometry to demonstrate that the nFh12 protein complex is, in fact, a complex of fatty acid binding proteins. Five long-chain saturated and unsaturated fatty acids were detected. The most abundant were palmitic acid (38%), stearic acid (24%), and oleic acid (13%). These fatty acid molecules do not have covalent bonds attached to the protein molecule. Because both nFh12 and Sm14 protect mice against challenge infection with F. hepatica and S. mansoni, it is possible that they have common protective epitopes in which fatty acids could be involved. Further studies are in progress to determine the chemical nature of these potential common epitopes.

Animals↗
PubMed1980

Effect of histamine on bovine milk fatty acids.

Milk histamine content was monitored over the estrous cycle of several cows. Concentrations of histamine in the milk were maximal between days 0 and 1 and between days 4 and 7 of the estrous cycle. One quarter of a mammary gland of each of six cows was infused with 10 mg histamine free base. Milk samples were taken at 0, 4 and 10 hr, then analyzed for fatty acid composition. The 4-hr samples showed an increase in the proportion of short and medium length fatty acids, an increase in myristoleic, palmitoleic, oleic and linoleic acids and a decrease in stearic acid. The 10-hr samples showed a decrease in proportion of short and medium length fatty acids, a decrease in palmitic acid and an increase in stearic acid, while oleic acid and linoleic acid continued to increase from preinfusion. Linolenic acid showed no significant change during the experiment. Milk from one normal and one mastitic quarter of the mammary glands of several cows showed a significantly higher histamine content in mastitic milk than in normal milk.

Animals↗
PubMed2006

Dietary hydrogenated soybean oil affects lipid and vitamin E metabolism in rats.

Fatty acids containing stearic acid, which are found in hydrogenated fat, may have a detrimental effect on the cholesterol and triacylglycerol (TAG) content of plasma lipoproteins, and on the absorption of fatty acids and fat-soluble vitamins. The aim of our study was to examine the tissue concentration of lipids and vitamins A and E after feeding a hydrogenated soybean oil (HSO) diet to rats. Twenty male Sprague-Dawley rats were randomly divided into two groups, fed on coconut oil (control) and HSO, respectively in amounts corresponding to 15% of the total feed. Plasma total cholesterol, VLDL- and LDL-cholesterol, lipid peroxidation and daily excretion of the TAG and cholesterol in feces were higher in the HSO than in the control group. TAG values in plasma and liver, and HDL-cholesterol levels in plasma were lower in the HSO than in the control group. The same was true for phospholipids in plasma and for saturated fatty acids, mono- and polyunsaturated fatty acids levels in the liver and vitamin E in plasma, LDL and adipose tissue. The results of this study provide new evidence concerning the effect of dietary hydrogenated fat on lipid, TAG and vitamin E status, which are important for maintenance of good health. Consumption of dietary HSO may be associated with cardiovascular disease.

Animals↗
PubMed2006

[Analysis of constituents in urushi wax, a natural food additive].

Urushi wax is a natural gum base used as a food additive. In order to evaluate the quality of urushi wax as a food additive and to obtain information useful for setting official standards, we investigated the constituents and their concentrations in urushi wax, using the same sample as scheduled for toxicity testing. After methanolysis of urushi wax, the composition of fatty acids was analyzed by GC/MS. The results indicated that the main fatty acids were palmitic acid, oleic acid and stearic acid. LC/MS analysis of urushi wax provided molecular-related ions of the main constituents. The main constituents were identified as triglycerides, namely glyceryl tripalmitate (30.7%), glyceryl dipalmitate monooleate (21.2%), glyceryl dioleate monopalmitate (2.1%), glyceryl monooleate monopalmitate monostearate (2.6%), glyceryl dipalmitate monostearate (5.6%), glyceryl distearate monopalmitate (1.4%). Glyceryl dipalmitate monooleate isomers differing in the binding sites of each constituent fatty acid could be separately determined by LC/MS/MS.

Chromatography, Liquid↗
PubMed2000

[Atherosclerosis and nutrition].

Atherosclerosis is the main cause of mortality in industrialized countries and even in poorly developed ones. It is linked to age and gender and also to a number of well identified risk factors: lipids anomalies, arterial hypertension, diabetes, smoking and weight excess among others. Risk factors improvement significantly reduces cardiovascular events. It is evident that nutrition plays an important role as it can modulate the evolution of body weight and blood pressure. Nutrition is also able to reduce the prevalence and severity of hyperlipidemias and diabetes. Saturated fatty acids (excepted stearic acid), trans poly-unsaturated acids as well as cholesterol increase serum LDL-cholesterol. Mono- and poly-unsaturated and classical cis-mono-unsaturated acids do the opposite. N-3 poly-unsaturated acids reduce serum triglyceride levels and cardiovascular events. Carbohydrates with a low glycemic index are important determinants of serum HDL-cholesterol levels and reduce cardiovascular risk. Animal proteins bring essential amino-acids to the body but also saturated fats. It seems interesting to eat vegetal proteins among which those derived from soya look promising. Our diet will include enough fiber and phytosterols-containing margarines look interesting as well. Modest alcohol consumption improves cardiovascular mortality in the majority of the prospective studies.

Arteriosclerosis↗
PubMed1975

Tissue lipid composition in fatty liver and kidney syndrome in chicks.

The lipid composition of the liver, kidneys, heart and adipose tissue of chicks affected by the fatty liver and kidney syndrome were analysed. Livers and kidneys showed 400 to 500 per cent increases in heart lipid levels. Liver and kidney triglycerides contained increased proportions of mono-unsaturated fatty acids, mainly palmitoleic acid, at the expense of the saturated fatty acids, mainly stearic acid. Phospholipid and adipose tissue fatty acid composition were not markedly altered. The abnormalities were regressing in birds recovering from the syndrome.

Adipose Tissue↗
PubMed1975

Certain physiochemical properties of uterine tubal fluid, follicular fluid, and blood plasma in the mare.

Uterine tubal fluids were collected twice a day from mares for 5 consecutive estrous cycles between March 15 and September 1. Follicular fluids were aspirated from the follicles of exteriorized ovaries of 3 mares between days 2 and 5 of estrus. Uterine tubal fluid and follicular fluid were analyzed for osmolarity, dry matter, total lipids, total free fatty acids, glucose, fructose, and lactic acid. Blood samples were collected (jugular venipuncture) throughout the estrous cycle, and the same physical and biochemical analyses were made on blood plasma. A difference (P less than 0.01) was found for osmolarity between uterine tubal fluids collected during estrus and those collected during anestrus. The osmolarity of uterine tubal fluid during anestrus was greater than that of blood plasma; follicular fluid was similar in osmolarity to blood plasma. The dry matter in blood plasma was greater (P less than 0.01) than that in either uterine tubal fluid or follicular fluid. Cyclic variations in dry matter content were not observed in uterine tubal fluid. Total lipids in blood plasma and follicular were greater (P less than 0.01) than those in uterine tubal bluid. The concentration of total lipid in uterine tubal fluid was similar during estrus and anestrus. Myristic acid (C14:0) in blood plasma and myristoleic acid (C14:1) in uterine tubal fluid were the only free fatty acids that had cyclic variation. The fatty acids in the greatest concentration in uterine tubal fluid and blood plasma were palmitic acid (C16:0) and linoleic acid (C18:2). Concentrations of linoleic acid and stearic acid (C18:0) were greater (P less 0.01) in follicular fluid than in uterine tubal fluid or blood plasma. Only trace amounts of glucose were detected in uterine tubal fluid, whereas a considerable amount of glucose was found in follicular fluid. Fructose was not detected in any of the fluids. Lactic acid concentrations did not differ between estrus and anestrus. Lactic acid concentration was significantly greater (P less than 0.01) in uterine tubal fluids and follicular fluids than in blood plasma.

Animals↗
PubMed2000

[Seed growth characteristics of Ginkgo biloba and its physiological change].

The length, width, volume and weight of Ginkgo biloba seed were measured, and the concentrations of water, sugars, fatty acids and amino acids in seed growth process were analyzed. A typical "S" seed growth curve was found, and the length, width, volume, weight and absolute water content all showed the similar changes during growing period. With the growing of ssed, the concentrations of physiological substances in seeds showed regular changes and had their own characteristics. The total amount of sugars appeared to be an increasing trend at the later stage of seed growth, indicating that sugars are the main nutrition substance accumulated in seeds. The concentrations of various substances in matured seeds were starch 8.4%, glucose 6.7%, fructose 4.2%, polysaccharide 0.02%, disaccharide 0.01%, myristic acid 10.6%, palmitic acid 4.1%, flax acid 2.4%, stearic acid 1.9%, oleic acid 1.1%, and linoleic acid 0.4%. Fifteen types of free amino acids were detected in matured seeds, with total content of 1.56 g.100 g-1FW. Among them, lysine aspartic acid, alanine, arginine, histidine, glutamic acid, and isoleucine were dominant, and their concentrations were 0.287%, 0.163%, 0.136%, 0.133%, 0.123%, 0.115%, 0.095%, respectively.

Amino Acids↗