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PubMed1999

Effect of fatty acids on the permeation of melatonin across rat and pig skin in-vitro and on the transepidermal water loss in rats in-vivo.

Transdermal delivery of melatonin would be advantageous in the treatment of sleep disorders considering the short biological half-life of melatonin and its variable bioavailability via the oral route. This study looked at suitable penetration enhancers for the transdermal permeation of melatonin. The permeation of melatonin was enhanced by all saturated and unsaturated fatty acids across both rat and porcine skin. There was a parabolic relationship between the carbon chain length of saturated fatty acids and the enhancement of melatonin permeation across rat and porcine skin. For rat skin, the maximum flux was observed with undecanoic acid (45.33 microg cm(-2) h(-1)) which enhanced the flux of melatonin 8.6 times compared with the control, whereas lauric acid produced the maximum flux of melatonin (24.98 microg cm(-2) h(-1); 4-7 times) across porcine skin. An increase in the number of double bonds in cis-9-octadecanoic acid increased the flux of melatonin across rat skin. In contrast, with porcine skin, the flux of melatonin decreased as the number of double bonds increased, although the flux values were not statistically significant. Treatment of rats with undecanoic acid, oleic acid and linolenic acid for 3 h using Hill top chamber enhanced the transepidermal water loss significantly. The maximum transepidermal water loss was observed with undecanoic acid and linolenic acid among saturated and unsaturated fatty acids, respectively. Nonanoic acid and myristic acid did not cause a significant change in the transepidermal water loss. The enhancement effect of saturated fatty acids on the permeation of melatonin was dependent on the chain-length of the fatty acid in both rat and porcine skin. While an increase in the number of double bonds in the fatty acid increased the flux of melatonin in rat skin, no significant difference in the flux was observed with porcine skin. The permeation enhancement of melatonin by saturated and unsaturated fatty acids across rat skin was significantly higher than that of porcine skin. A positive correlation was observed between the permeation enhancement effect of the fatty acids across rat skin in-vitro and the transepidermal water loss in rats in-vivo, suggesting that there is a similarity in the mechanism by which fatty acids enhance the permeation of melatonin and in the enhancement of transepidermal water loss. We conclude that saturated fatty acids such as undecanoic acid or lauric acid which showed maximum permeation across rat and porcine skin, respectively, may be used as potential penetration enhancers in the development of a transdermal delivery system for melatonin.

Acids, Acyclic↗
PubMed2005

Analysis of the fatty acid from Bupleurum Chinense DC in China by GC-MS and GC-FID.

Fatty acid of the root of the medicinal plant of Bupleurum Chinense DC in China has been investigated by gas chromatography combined with mass spectroscopy. After methyl-esterification, eight fatty acid compositions were identified by GC-MS. A simple and rapid determination of the fatty acid has been firstly developed by GC-FID. The derivatization condition was investigated in order to validate this method. Palmitic acid, palmitoleic acid, oleic acid and linoleic acid were analyzed simultaneously by internal standard method. The validity of method has been examined both experimentally with good recovery, intra-assay precisions and linearity. The quick and accurate method of capillary gas chromatography could be used for the analysis of the fatty acid from Bupleurum Chinense DC.

Bupleurum↗
PubMed2006

Nutrition and cancer risk: an overview.

The role of diet in cancer is a major public health issue Foods associated with a low risk of cancer are those typically included in the so-called Mediterranean diet, which is also associated with low mortality rates from cardiovascular disease. Implementing such a diet would involve increasing the consumption of fruits, vegetables, cereals, whole-grain foods and fish, while reducing the intake of refined carbohydrates and red meat. In addition, olive oil should replace saturated fats. Omega-3 fatty acids found in fish inhibit the growth in vitro of colon, breast and prostate cancers. Fibre can bind bile acids, which produce carcinogenic metabolites, and fermented fibre produces volatile fatty acids that can protect against colon cancer. It has been hypothesized that the anti-cancer actions of olive oil may relate to the ability of its mono-unsaturated fatty acid, oleic acid, to regulate oncogenes.

Diet, Mediterranean↗
PubMed2002

Influence of Tween 80 on lipid metabolism of an Aspergillus niger strain.

Addition of 0.1% of nonionic surface-active Tween 80 to a medium optimized for pectolytic enzyme production of Aspergillus niger increased the amount of enzymes excreted by 70%. In the presence of Tween 80 the amount of sterol esters and triacylglycerols was increased. During the course of cultivation the amounts of precursors for ergosterol biosynthesis diminished with an increase of ergosterol. A. niger incorporated cholesterol from the medium, partly converting it to cholesterol esters. Sterol esters were formed only with selected fatty acids. Oleic acid, the hydrophobic part of Tween 80, was mainly incorporated in phospholipids and glycolipids.

Aspergillus niger↗
PubMed1988

Effect of phosphatidyl inositol on progesterone receptors in rat uterine cytosol.

It was reported that unsaturated long chain fatty acids, such as arachidonic acid, oleic acid and docosahexaenoic acid inhibit the binding between progesterone and estrogen receptors and steroid hormones. Most of the long chain fatty acids are contained in phospholipids within the cells. The effect of phospholipids on the binding between R5020 and progesterone receptors was studied. Phosphatidyl ethanolamine and sphingomyelin had no effect on binding, but phosphatidyl inositol and phosphatidyl serine inhibited the binding 53% and 34% respectively. The effect of phosphatidyl inositol on the binding between R5020 and progesterone receptors was dose dependent. Scatchard analysis revealed that the addition of phospholipid markedly decreased the number of binding sites from 1398 fmol/mgp to 258 fmol/mgp, but the dissociation constant was little affected.

Animals↗
PubMed1986

Lipid analysis of immature pig oocytes.

The detailed analysis of the lipid composition of immature pig oocytes represents the first such study carried out on mammalian eggs. In order to undertake a large scale lipid analysis using conventional extraction and chromatographic techniques a procedure for mass harvesting relatively large numbers of pig oocytes (200-300 oocytes/ovary) was developed. The study revealed that triacylglycerol was the major lipid component (100.71 nmol/mg protein) followed by cholesterol (32.71 nmol/mg protein). Phosphatidylcholine constituted the major phospholipid component (27.83 nmol/mg protein). Pig oocytes contained relatively low proportions of phosphatidylethanolamine (16.41% total phospholipid) and relatively high proportions of lysophosphatidylcholine (4.68% total phospholipid). The free fatty acid pattern was strikingly similar to the fatty acid composition of phosphatidylcholine. This observation, in conjunction with the observed high levels of lysophosphatidylcholine and the low ratio of phosphatidylethanolamine to phosphatidylcholine, suggests a fast rate of phospholipid turnover in the immature pig oocyte. Analysis of fatty acids esterified to the individual phospholipids and neutral lipids has shown that in all the classes examined, particularly in the neutral lipid fractions, there are high levels of the saturated fatty acid palmitic acid (16:0) and the monounsaturated fatty acid oleic acid (18:1). Triacylglycerol, free fatty acids and most of the phospholipids, particularly phosphatidylethanolamine, are considerably enriched in n-6 polyunsaturated fatty acids, specifically linoleic (18:2), arachidonic (20:4) and adrenic (22:4) acids. This may indicate an ability of oocytes to synthesize prostaglandins and leukotrienes. The results show that the lipid environment of the immature pig oocyte may be adapted to the highly specialized requirements of the cell, promoting growth and development with a potential role in the regulation of maturation.

Animals↗
PubMed1993

Effect of arachidonic acid on twitch tension of the rat phrenic nerve-diaphragm.

Recent studies have demonstrated that unsaturated fatty acids are involved in the regulation of neuroeffector function. I have extended these studies by examining the effect of arachidonic acid on neuromuscular function in vitro using the rat phrenic nerve-diaphragm preparation. Arachidonic acid caused a time-and dose-dependent reduction in indirectly stimulated twitch tension, but had no effect on directly stimulated twitch tension. Linoleic acid and linolenic acid also reduced indirectly stimulated twitch tension, whereas stearic acid, oleic acid and arachidic acid had no effect. None of three blockers of arachidonic acid metabolism, the cyclooxygenase inhibitor indomethacin, the lipoxygenase inhibitor nordihydroguaiaretic acid or the cytochrome P-450 inhibitor ketoconazole, altered the effect of arachidonic acid on twitch tension. The free radical scavenger superoxide dismutase eliminated the inhibitory effect of arachidonic acid on twitch tension, suggesting that superoxide anion played a role in arachidonic acid's action.

Animals↗
PubMed1999

Long-term elevation of free fatty acids leads to delayed processing of proinsulin and prohormone convertases 2 and 3 in the pancreatic beta-cell line MIN6.

To explore the role of chronically elevated free fatty acids (FFAs) in the pathogenesis of the hyperproinsulinemia of type 2 diabetes, we have investigated the effect of FFAs on proinsulin processing and prohormone convertases PC2 and PC1/PC3 in MIN6 cells cultured in Dulbecco's modified Eagle's medium with or without 0.5 mmol/l FFA mixture (palmitic acid:oleic acid = 1:2). After 7 days of culture, the percent of proinsulin in FFA-exposed cells was increased (25.9 +/-0.3% intracellular and 75.4 +/- 1.2% in medium vs. 13.5 +/-0.2 and 56.2 +/- 4.1%, respectively, in control cells). The biosynthesis and secretion of proinsulin and insulin were analyzed by comparing the incorporation of [3H]Leu and [35S]Met. In pulse-chase studies, proinsulin-to-insulin conversion was inhibited, and proinsulin in the medium was increased by 50% after 3 h of chase, while insulin secretion was decreased by 50% after FFA exposure. Levels of cellular PC2 and PC3 analyzed by Western blotting were decreased by 23 and 15%, respectively. However, PC2, PC3, proinsulin, and 7B2 mRNA levels were not altered by FFA exposure. To test for an effect on the biosynthesis of PC2, PC3, proinsulin, and 7B2, a protein required for PC2 activation, MIN6 cells were labeled with [35S]Met for 10-15 min, followed by a prolonged chase. Most proPC2 was converted after 6 h of chase in control cells, but conversion was incomplete even after 6 h of chase in FFA-exposed MIN6 cells. Media from chase incubations showed that FFA-exposed cells secreted more proPC2 than controls. Similar inhibitory effects were noted on the processing of proPC3, proinsulin, and 7B2. In conclusion, prolonged exposure of beta-cells to FFAs may affect the biosynthesis and posttranslational processing of proinsulin, PC2, PC3, and 7B2, and thereby contribute to the hyperproinsulinemia of type 2 diabetes. The mechanism of inhibition of secretory granule processing by FFAs may be through changes in Ca2+ concentration, the pH in the secretory granules, and/or other factors that may influence the activation and function of the convertases.

Animals↗
PubMed2003

Effects of forage and sunflower oil levels on ruminal biohydrogenation of fatty acids and conjugated linoleic acid formation in beef steers fed finishing diets.

Six Hereford steers (295 kg) cannulated in the proximal duodenum were used to evaluate the effects of forage and sunflower oil level on ruminal biohydrogenation (BH) and conjugated linoleic acid (CLA) outflow. Steers were fed one of six treatment diets in a 3 x 2 factorial arrangement of treatments (grass hay level: 12, 24, or 36% of DM; and sunflower oil level: 2 or 4% of DM) in a 6 x 6 Latin square design. The remainder of the diet was made up of steam rolled corn and protein/mineral supplement. Duodenal samples were collected for 4 d following 10-d diet adaptation periods. Data were analyzed with animal, period, forage level, sunflower oil level, and two-way interaction between forage and sunflower oil level in the model. Dry matter intake showed a quadratic response (P < 0.04), with an increase in DMI as forage level increased from 12 to 24% followed by a decrease in DMI when 36% forage was fed. Flow of fatty acids at the duodenum was higher (P < 0.03) for 4 vs. 2% sunflower oil diets, and similar among forage levels. Apparent ruminal digestibility of NDF increased in a linear manner (P < 0.04) as dietary forage level increased. Ruminal BH of dietary unsaturated 18-C fatty acids, oleic acid, and linoleic acid increased linearly (P < 0.05) as dietary forage level increased. Linoleic acid BH tended (P < 0.07) to be greater for 4 than 2% sunflower oil level. Duodenal flow of pentadecyclic, stearic, linolenic, and arachidic acids increased linearly (P < 0.05) as dietary forage level increased from 12 to 36%. Duodenal flow of linoleic acid decreased in a linear manner (P < 0.03) with increasing dietary forage level. Flow of trans-10 octadecenoate decreased linearly (P < 0.03) as dietary forage level increased, whereas trans-11 vaccenic acid flow to the duodenum increased (P < 0.01) linearly with increased dietary forage. Dietary forage or sunflower oil levels did not alter the outflow of cis-9, trans-11 CLA. Flows of cis-11, trans-13, and cis-9, cis-11 CLA increased linearly (P < 0.05) with increased dietary forage. Flows of cis-11, cis-13, and trans-11, trans-13 CLA decreased linearly (P < 0.05) with increased dietary forage. Increasing dietary forage levels from 12 to 36% in beef cattle finishing diets increased BH of unsaturated 18-C fatty acid and outflow of trans-11 vaccenic acid to duodenum without altering cis-9, trans-11 CLA outflow.

Animal Feed↗
PubMedDate not supplied

Effect of surfactants on the stability of modified egg-yolk phosphatidyl choline liposomes.

Disintegration by surfactants on egg-yolk phosphatidyl choline (PC) vesicles, stabilized with polycholesteryl methacrylate and carboxy methyl chitosan, was investigated by measuring the amount of marker dye (bromothymol blue) released from the vesicles. In all the studies at pH 7.4 anionic and nonionic surfactants caused vesicle disintegration at low concentrations while cationic surfactants produced breakdown of vesicles at high concentrations. It was found that the modified liposomes disintegrated in the following order: Polymeric liposomes less than carboxymethyl chitosan coated/stearic acid/oleic acid containing PC liposomes less than cholesteryl methacrylate monomer containing PC liposomes/PC liposomes Polymeric liposomes were found to be the most stable compared with all other types. This may be explained due to the filling of the pores in the lipid structure which in turn block the surfactant penetration into phospholipid bilayers. In contrast to unsaturated fatty acid (oleic acid) saturated fatty acid (stearic acid) containing liposomes are more stable.

Drug Carriers↗
PubMed1998

Effect of cod-liver oil extract on the buccal permeation of ergotamine tartrate.

Ergotamine tartrate (ET) is used clinically in the treatment of migraines. However, the bioavailability of ET is rather poor following oral administration. Therefore, we tried to improve ET delivery using buccal administration. The purpose of this study was to investigate the characteristics of the permeation of ET through the hamster cheek pouch in vitro using a two-chamber diffusion cell, and to evaluate the effect of permeation enhancers on the transbuccal delivery of ET. Cod-liver oil extract (CLOE), polyoxyethylene hydrogenated castor oil (HCO 60), sodium glycocholate (GC), and sodium caprate (CA) were selected as premeation enhancers considering their low irritancy of the mucosa. When the enhancers were added to the donor cell at a 5% concentration each, the ET permeation rate markedly increased compared with that in a control not containing enhancer. Among these enhancers, CLOE exhibited the greatest effect. Because CLOE is composed of 16 kinds of fatty acids, the enhancement action of each of the major components was separately determined. As major fatty acids, palmitic acid, oleic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) were selected and their enhancing effects were studied. The enhancing effect of each fatty acid was significantly lower than that of CLOE.

Animals↗
PubMed1993

Effects of vegetable oils and C18-unsaturated fatty acids on plasma ethanol levels and gastric emptying in ethanol-administered rats.

The effects of vegetable oils (soybean oil and coconut oil) and C18-unsaturated fatty acids (oleic acid, C18:1; linoleic acid, C18:2; linolenic acid, C18:3) on plasma ethanol levels in male rats (6 weeks old) were investigated. Vegetable oils decreased and delayed the peak of plasma ethanol concentration: a dose-response to vegetable oils was observed in the concentration and time to maximum concentration of plasma ethanol but no change in disappearance time. These phenomena were observed in two conditions: 1) oral administration of vegetable oils before oral intubation of ethanol and 2) simultaneous oral administration of vegetable oils and ethanol. Similar responses were obtained in three C18-unsaturated fatty acids. No changes in hepatic alcohol and aldehyde dehydrogenase isozyme (high Km and low Km) activities were observed. The remaining rate of ethanol in stomach was significantly higher with administration of vegetable oils or linoleic acid. A high negative correlation between the maximum plasma ethanol concentration and the remaining rate of ethanol in stomach was found. These results suggest that the slowing of the gastric emptying is a major mechanism for the decreasing and delaying effects on plasma ethanol levels by vegetable oils. The present paper also suggests that fatty acids may participate in the decreasing and delaying actions on the peak of plasma ethanol concentration by vegetable oils.

Administration, Oral↗
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↗
PubMed1990

The influence of supplemental corn oil and free fatty acids on the reproductive performance of Japanese quail (Coturnix coturnix japonica).

An experiment was conducted to evaluate the effects of dietary corn oil (CO) and commercial free fatty acids on the fatty acid composition of blood plasma and egg yolk lipids and on the reproductive performance of Japanese quail. When quail were fed a semi-purified low-fat basal mix, the substitution of 3% of CO for corn starch (CS) improved egg weight (11.2 versus 10.8 g), reduced late embryonic mortality (16.7 versus 28.4%), and improved hatchability (75.7 versus 64.1%). Diets in which palmitic acid or oleic acid were substituted on a weight basis for 3% of CS performed as well as those in which CO was used. When linoleic acid replaced 3% of CS, late embryonic mortality was reduced (13.7 versus 28.4%) and hatchability was improved (80.1 versus 64.1%), but fertility was depressed (85.8 versus 93.6%). The substitution of linolenic acid for 3% of CS depressed feed consumption, body weight, and egg weight relative to the low-fat CS diet and did not improve the low 18-day embryonic livability and low hatchability. The fatty acid compositions of plasma and yolk were influenced by the lipid composition of the diets. Quail fed 3% of CO deposited more linoleic acid in the egg than those fed 3% of linoleic acid (15.2 versus 11.7%). Thus, quail fed a simplified basal breeder diet containing .6% of linoleic acid showed decreased embryonic livability and hatchability and these parameters achieved normal levels in response to the substitution of 3% of either CO, palmitic acid, oleic acid, or linoleic acid for CS.

Animals↗
PubMed1976

Effect of some lipids on the activity of renin in vitro.

A partially purified bovine renin preparation and a homologous renin substrate were used to study the effect of some lipids on the amount of angiotensin formed. It was found that lecithin and the detergents used (deoxycholate and sodium dodecylate) inhibited the renin activity. Palmitic acid, oleic acid and cholesterol had no distinct effect. On the other hand, the reaction was enhanced by prostaglandins E2 and F2alpha.

Angiotensin II↗
PubMed1999

Identification and molecular characterization of acyl-CoA synthetase in human erythrocytes and erythroid precursors.

Full-length cDNA species encoding two forms of acyl-CoA synthetase from a K-562 human erythroleukaemic cell line were cloned, sequenced and expressed. The first form, named long-chain acyl-CoA synthetase 5 (LACS5), was found to be a novel, unreported, human acyl-CoA synthetase with high similarity to rat brain ACS2 (91% identical). The second form (66% identical with LACS5) was 97% identical with human liver LACS1. The LACS5 gene encodes a highly expressed 2.9 kb mRNA transcript in human haemopoietic stem cells from cord blood, bone marrow, reticulocytes and fetal blood cells derived from fetal liver. An additional 6.3 kb transcript is also found in these erythrocyte precursors; 2.9 and 9.6 kb transcripts of LACS5 are found in human brain, but transcripts are virtually absent from human heart, kidney, liver, lung, pancreas, spleen and skeletal muscle. The 78 kDa expressed LACS5 protein used the long-chain fatty acids palmitic acid, oleic acid and arachidonic acid as substrates. Antibodies directed against LACS5 cross-reacted with erythrocyte membranes. We conclude that early erythrocyte precursors express at least two different forms of acyl-CoA synthetase and that LACS5 is present in mature erythrocyte plasma membranes.

Adult↗
PubMedDate not supplied

The influence of different varieties of olive oil on N-methylnitrosourea(NMU)-induced mammary tumorigenesis.

Several epidemiological and animal model studies suggest that consumption of olive oil, which is rich in the monounsaturated fatty acid, oleic acid (OA, C18:, n-9) may reduce the risk of breast cancer. There are however, a wide variety of olive oils in the marketplace with levels of OA ranging from a low of 50% to a high of 80% OA. The purpose of this rodent model study was to determine whether the level of OA in olive oil is a key determinant of its protective effects. We compared the inhibitory effects among three different types of olive oil containing 54, 70 and 80% OA and 20, 15 and 5% linoleic acid (LA), respectively, corn oil and a store bought olive oil, using the NMU-induced rat mammary tumor model. While little difference was found in total mammary tumor yields, a differential effect was found in the histological type of tumors formed. Olive oil containing 80% OA and 5% LA exhibited the lowest level of adenocarcinomas and the highest level of the more benign adenocarcinoma arising from within a fibroadenoma. While the reasons for this effect remain to be clarified, these results suggest that future studies on the health benefits of olive oil should take into account the type as well as the amount of olive oil.

Animals↗
PubMed2000

The study of nonspecific internalization of cholesteryl esters by the Hep G2 hepatoma cells.

The cholesteryl oleate-POPC dispersions (1:3, mol/mol, mean particle size 110+/-20 nm) were taken up by the human hepatoma line Hep G2 cells via endocytosis. Internalization of the cholesteryl oleate-POPC dispersions by Hep G2 cells was dependent on the incubation time and dispersion concentration. At the cholesteryl oleate concentration 100 microM, its total uptake and internalization were found to be 1.5 nmol and 0.8 nmol per 1 mg of cell protein/24 h, respectively. Intracellular cleavage of the cholesteryl oleate incorporated in dispersions resulted in accumulation of free cholesterol capable of being released into the medium and metabolized to water-soluble polar products, presumably bile acids; oleic acid released is, apparently, involved in biosynthesis of triacylglycerides. The low-density lipoprotein receptor is not involved in internalization of lipid dispersions, and the presence of the cholesteryl oleate-POPC dispersions has no effect on the receptor-dependent internalization of cholesteryl esters of the low-density lipoproteins. The obtained data allow us to consider nonspecific internalization of cholesteryl esters by hepatocytes as a substantial part of the nonpolar lipid clearance.

Biological Transport↗