linoleic-acid and elaidic-acid

Obese hypertensives have increased nonesterified fatty acids (NEFAs) and alpha-adrenergic vascular reactivity. Raising NEFAs locally with intralipid and heparin augments dorsal hand venoconstrictor responses to phenylephrine, an alpha(1)-adrenoceptor agonist. The enhanced venoconstrictor responses were reversed by indomethacin. The findings suggest that raising NEFAs leads to the generation of cyclooxygenase (COX) product(s) that enhance vascular reactivity. To test this notion, 6-keto-PGF(1alpha) and TxB(2), the stable metabolites of prostaglandin H(2) (PGH(2)); prostacyclin (PGI(2)); and thromboxane (TxA(2)), were measured approximately 1.5 to 2 cm downstream of a dorsal hand vein infusion of intralipid and heparin (n=10) or saline and heparin (n=5) for 2 hours each. During the third hour, intralipid and heparin (experimental) and saline and heparin (control) were continued, and either saline (control) or indomethacin (intervention) were infused. Intralipid and heparin raised local 6-keto PGF(1alpha) concentrations by 350% to 500% (P<0.005), but saline and heparin did not (P=NS). TxB(2) levels did not change significantly with any infusion. Infusion of indomethacin during the third hour of intralipid and heparin lowered plasma 6-keto-PGF(1alpha) (P<0.05), whereas infusion of saline with intralipid and heparin did not (P=NS). Oleic and linoleic acids at 100 micromol/L, increased 6-keto-PGF(1alpha) in vascular smooth muscle cells (VSMCs) through a protein kinase C and extracellular, signal-regulated kinase independent pathway. However, oleic and linoleic acids increased intracellular Ca(2+) in VSMCs. The data indicate that NEFAs induce the production of COX products, perhaps via Ca(2+)-dependent activation of phospholipase A(2). The COX product(s) may contribute to increased vascular alpha-adrenergic reactivity among insulin-resistant individuals when NEFAs are elevated.

Topics: 6-Ketoprostaglandin F1 alpha; Adult; Animals; Calcium; Cells, Cultured; Fat Emulsions, Intravenous; Female; Hand; Heparin; Humans; Indomethacin; Linoleic Acid; Male; Middle Aged; Muscle, Smooth, Vascular; Oleic Acid; Oleic Acids; Rats; Stearic Acids; Thromboxane B2; Time Factors; Veins

Dietary fatty acids that are more prone to oxidation than to storage may be less likely to lead to obesity.. The aim of this study was to determine the effect of chain length, degree of unsaturation, and stereoisomeric effects of unsaturation on the oxidation of individual fatty acids in normal-weight men.. Fatty acid oxidation was examined in men consuming a weight-maintenance diet containing 40% of energy as fat. After consuming the diet for 1 wk, subjects were fed fatty acids labeled with (13)C in the methyl or carboxyl position (10 mg/kg body wt). The fatty acids fed in random order were laurate, palmitate, stearate, oleate, elaidate (the trans isomer of oleate), linoleate, and linolenate blended in a hot liquid meal. Breath samples were collected for the next 9 h and the oxidation of each fatty acid was assessed by examining liberated (13)CO(2) in breath.. Cumulative oxidation over the 9-h test ranged from a high of 41% of the dose for laurate to a low of 13% of the dose for stearate. Of the 18-carbon fatty acids, linolenate was the most highly oxidized and linoleate appeared to be somewhat conserved. (13)C recovery in breath from the methyl-labeled fatty acids was approximately 30% less than that from the carboxyl-labeled fatty acids.. In summary, lauric acid is highly oxidized, whereas the polyunsaturated and monounsaturated fatty acids are fairly well oxidized. Oxidation of the long-chain, saturated fatty acids decreases with increasing carbon number.

Topics: Adult; alpha-Linolenic Acid; Breath Tests; Calorimetry, Indirect; Carbon Isotopes; Dietary Fats; Fatty Acids; Humans; Lauric Acids; Linear Models; Linoleic Acid; Male; Mass Spectrometry; Oleic Acid; Oleic Acids; Oxidation-Reduction; Oxygen Consumption; Palmitic Acid; Pilot Projects; Reproducibility of Results; Stearic Acids

The objective of this study was to compare the effect of linoleic acid (cis,cis-C18:2) with that of its hydrogenation products stearic acid (C18:0) and elaidic acid (trans-C18:1) on blood pressure levels in normotensive humans. We therefore measured the effects of these fatty acids on systolic and diastolic blood pressure in 30 women and 25 men. Three strictly controlled experimental diets were supplied to every subject for 3 weeks each, in different order (multiple cross-over). The composition of the three diets was constant, except for 8% of daily energy, which was provided by either linoleic acid, stearic acid, or monounsaturated trans fatty acids. The statistical power for detecting a true difference between two diets of 3 mmHg in systolic and diastolic blood pressure was over 90%. Mean systolic/diastolic blood pressure at the end of the dietary periods was 114/69 mmHg on the linoleic acid diet, 113/70 on the stearic acid diet, and 113/69 on the trans fatty acid diet. No significant differences were observed in blood pressure levels after 3 weeks on each diet. We conclude that a major increase in the intake of linoleic acid at the expense of stearic acid or trans fatty acids has no effect on blood pressure in normotensive young women and men.

Topics: Adult; Blood Pressure; Diet; Feeding Behavior; Female; Humans; Linoleic Acid; Linoleic Acids; Male; Middle Aged; Oleic Acid; Oleic Acids; Stearic Acids; Stereoisomerism

To determine Industrially-Produced Trans fatty acids (IP-TFAs) distribution of Lebanese traditional foods, especially regarding Elaidic acid (EA; 9t18:1) and Linolelaidic acid (LEA; 9t12t18:2), a mapping exercise was enrolled between January 2019 and April 2021 in which 145 food samples of three categories (traditional dishes, Arabic sweets, and market food products) were analyzed using Gas chromatography methods. Results showed that about 93% of the products tested in Lebanon, between 2019 and 2021, met the World Health Organization recommendations, while about 7% exceeded the limit. The mean level of the IP-TFAs Elaidic and Linolelaidic acid in most Traditional dishes (0.9%), Arabic sweets (0.6%), butter and margarine (1.6%), and market foods (0.52%) were relatively low compared with other countries. Despite that, the relative impact of IP-TFAs on heart diseases mortality in Lebanon is limited but unambiguously still substantial. The persistence of food products with high IP-TFAs levels threatens the health of Lebanese people. Fortunately, this problem is fairly easy to solve in Lebanon via proper legislation.

Topics: Butter; Food; Industry; Linoleic Acid; Oleic Acids; Snacks; Trans Fatty Acids

There has been controversial evidence regarding the relationship between isomers of circulating trans-fatty acids (TFAs) and mortality. This study aimed to ascertain the relationships between plasma TFAs and overall or cause-specific mortality of the general population in two independent subsets from the US National Health and Nutrition Examination Survey (1999-2000 and 2009-2010 cycles).. Plasma TFA isomers (C16:1n-7t, C18:1n-7t, C18:1n-9t and C18:2n-6,9t) in 3439 adults free of cancer or severe cardiovascular disease were analyzed by gas chromatography/mass spectrometry. Overall, 259 died among 1376 individuals over a median follow-up of 15.6 years in the 1999-2000 cycle, and 105 died in the latter subset of 2063 subjects during a median of 5.9 years. Cox proportional hazards regression was conducted to estimate the hazard ratios of mortality. The main isomer of industrially derived TFAs, elaidic acid (C18:1n-9t) was considerably associated with long-term total mortality in the 1999-2000 cycle after adjusting for confounders, with a 54% increase in the top tertile compared with the bottom one. However, the association disappeared with halving C18:1n-9t by 2009-2010. In contrast, neither of the ruminant-derived TFAs (C16:1n-7t and C18:1n-7t) suggested any inverse correlations with all-cause death, mortality due to heart disease, cancer or other causes.. The major isomer of industrial TFAs, the higher circulating C18:1n-9t might be associated with increased long-term mortality. The associations with death risk turned slight with the reduction of TFAs consumption by half. However, dietary guidelines should rigorously identify the healthy effect of animal TFAs consumption.

Topics: Adult; Cause of Death; Diet; Eating; Fatty Acids, Monounsaturated; Female; Follow-Up Studies; Gas Chromatography-Mass Spectrometry; Humans; Linoleic Acid; Male; Middle Aged; Mortality; Nutrition Surveys; Oleic Acids; Proportional Hazards Models; Prospective Studies; Risk Factors; Time Factors; Trans Fatty Acids; United States

trans-Fatty acids (TFAs) are unsaturated fatty acids that contain one or more carbon-carbon double bonds in trans configuration. Epidemiological evidence has linked TFA consumption with various disorders, including cardiovascular diseases. However, the underlying pathological mechanisms are largely unknown. Here, we show a novel toxic mechanism of TFAs triggered by DNA damage. We found that elaidic acid (EA) and linoelaidic acid, major TFAs produced during industrial food manufacturing (so-called as industrial TFAs), but not their corresponding cis isomers, facilitated apoptosis induced by doxorubicin. Consistently, EA enhanced UV-induced embryonic lethality in C. elegans worms. The pro-apoptotic action of EA was blocked by knocking down Sab, a c-Jun N-terminal kinase (JNK)-interacting protein localizing at mitochondrial outer membrane, which mediates mutual amplification of mitochondrial reactive oxygen species (ROS) generation and JNK activation. EA enhanced doxorubicin-induced mitochondrial ROS generation and JNK activation, both of which were suppressed by Sab knockdown and pharmacological inhibition of either mitochondrial ROS generation, JNK, or Src-homology 2 domain-containing protein tyrosine phosphatase 1 (SHP1) as a Sab-associated protein. These results demonstrate that in response to DNA damage, TFAs drive the mitochondrial JNK-Sab-ROS positive feedback loop and ultimately apoptosis, which may provide insight into the common pathogenetic mechanisms of diverse TFA-related disorders.

Topics: Adaptor Proteins, Signal Transducing; Animals; Apoptosis; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Cell Line, Tumor; DNA Fragmentation; Doxorubicin; Embryo, Nonmammalian; Feedback, Physiological; Gene Expression Regulation; Guanine Nucleotide Exchange Factors; HEK293 Cells; HeLa Cells; Human Umbilical Vein Endothelial Cells; Humans; JNK Mitogen-Activated Protein Kinases; Linoleic Acid; Mice; Mitochondria; Oleic Acids; Osteoblasts; Protein Tyrosine Phosphatase, Non-Receptor Type 6; RAW 264.7 Cells; Reactive Oxygen Species; RNA, Small Interfering; Ultraviolet Rays

Previous studies on health effects of trans fatty acids (TFA) have focused mainly on cardiovascular health. Little is known about the association of TFA with brain or mental health. In this study, we examined the associations of objectively-measured plasma TFA concentrations with depression in a large population-based cross-sectional study among U.S. adults.. We included 2136 non-pregnant participants aged 20 years or older from the National Health and Nutrition Examination Survey 2009-2010. Four major TFAs, including palmitelaidic acid (C16:1n-7t), elaidic acid (C18:1n-9t), vaccenic acid (C18:1n-7t), and linoelaidic acid (C18:2n-6t, 9t), were measured in fasting plasma using gas chromatography/mass spectrometry. Depressive symptoms were assessed using the validated Patient Health Questionnaire-9.. Participants with depressive symptoms had a higher plasma concentration of total TFA compared with those without depressive symptoms (6.6 vs 6.0 μmol/g lipids, P = 0.046). After adjustment for other major risk factors, the odds ratio (OR) of depressive symptoms comparing the highest with lowest tertile of TFAs was 1.44 (95% CI, 0.86-2.39) for total TFAs (P for trend 0.15). For each individual type of TFA, the corresponding OR was 1.78 (1.03-3.07) for elaidic acid (P for trend 0.049), 1.23 (0.76-2.00) for linoelaidic acid (P for trend 0.37), 1.19 (0.75-1.87) for palmitelaidic acid (P for trend 0.46), and 1.20 (0.75-1.94) for vaccenic acid (P for trend 0.43).. The cross-sectional study design limited causal inferences of the findings.. In a nationally representative population, plasma elaidic acid, a major trans fatty acid, was positively associated with depressive symptoms in adults. A positive but non-significant association of depressive symptoms was observed for total TFAs, linolelaidic acid, palmitelaidic acid, and vaccenic acid.

Topics: Adult; Aged; Cross-Sectional Studies; Depression; Fasting; Fatty Acids, Monounsaturated; Female; Gas Chromatography-Mass Spectrometry; Humans; Linoleic Acid; Male; Middle Aged; Nutrition Surveys; Oleic Acids; Patient Health Questionnaire; Risk Factors; United States

The effect of different individual TFA isomers on cardiovascular disease (CVD) has been a limited study, especially for stroke. We aimed to investigate the relationships between four major plasma TFA isomer (elaidic, vaccenic, palmitelaidic and linolelaidic acid) concentrations and the risk of CVD, stroke and non-stroke CVD. A cross-sectional study was conducted, utilising a nationally representative sample of US adults in the National Health and Nutrition Examination Survey. Among the 3504 participants, 304 participants self-reported CVD history. The highest quintile of elaidic acid intake was associated with a 233% higher CVD risk (p = .010). Adjusted for age, gender and race, palmitelaidic acid was associated with a decreased CVD risk, but the effect size was diminished in a subsequent analysis model. For stroke risk, we failed to identify any associations. In addition to elaidic acid, the health effect of palmitelaidic acid should be paid more attention in the future studies.

Topics: Adult; Aged; Aged, 80 and over; Body Mass Index; Cardiovascular Diseases; Cross-Sectional Studies; Diet; Fatty Acids, Monounsaturated; Female; Humans; Isomerism; Linoleic Acid; Male; Middle Aged; Nutrition Surveys; Oleic Acid; Oleic Acids; Risk Factors; Self Report; Trans Fatty Acids; United States; Young Adult

A diet high in trans-fatty acids (TFA) induces insulin resistance in rodent models and primates. However, previous epidemiological studies on the association between TFAs, based primarily on self-reported intake from the diet, and diabetes in humans have yielded conflicting results. Herein we examined the associations of objectively measured plasma TFA concentrations with diabetes in a large population-based study among US adults.. We included 3801 participants aged ≥20 years from the National Health and Nutrition Examination Survey 1999-2000 and 2009-10. Four major TFAs, namely palmitelaidic acid (C16:1 n-7t), elaidic acid (C18:1 n-9t), vaccenic acid (C18:1 n-7t), and linolelaidic acid (C18:2 n-6t, 9t), were measured in fasting plasma using gas chromatography-mass spectrometry. Diabetes was defined by self-reported physician diagnosis, plasma fasting glucose ≥126 mg/dL, or HbA1c ≥6.5%.. After adjustment for other major risk factors, the odds ratios (95% confidence intervals) of diabetes comparing the highest with lowest quintile of plasma TFAs was 2.19 (1.27-3.79) for total TFAs (P. In a nationally representative population, plasma TFAs, in particular elaidic acid, were positively associated with diabetes and biomarkers of glucose metabolism.

Topics: Adult; Blood Glucose; Diabetes Mellitus; Fasting; Fatty Acids, Monounsaturated; Female; Humans; Insulin; Insulin Resistance; Linoleic Acid; Male; Middle Aged; Nutrition Surveys; Oleic Acid; Oleic Acids; Risk Factors; Trans Fatty Acids; United States

The potential effects of 2 types of fatty acids on colorectal cancer (CRC) were assessed using cancer stromal cells. Linoleic acid (LA; C-18, n-6 unsaturated fatty acid) and elaidic acid (EA; C-18, trans acid), both known to affect colon carcinogenesis and cancer progression, were administered by gavage to BALB/c mice, which were inoculated with CT26 syngeneic colon cancer cells in the back. Both EA and LA treatments enhanced tumor growth and metastasis. EA and LA also increased the number of CD133-positive stromal cells in the tumor capsule. Importantly, those cancer cells at the tumor periphery, physically attached to CD133-positive stromal cells, also expressed CD133. These findings suggest that EA and LA might induce stemness in cancer cells through physical association and promote cancer metastasis.

Topics: AC133 Antigen; Animals; Carcinogenesis; Carrier Proteins; Cell Line, Tumor; Cell Movement; Colonic Neoplasms; Disease Models, Animal; Fatty Acids; GTP-Binding Proteins; Isografts; Linoleic Acid; Male; Mice; Mice, Inbred BALB C; Neoplasm Metastasis; Nuclear Proteins; Oleic Acid; Oleic Acids; RNA-Binding Proteins; Stromal Cells

Fatty acids (C6-C18) found in human amniotic fluid, colostrum, and maternal milk reduce behavioral indicators of experimental anxiety in adult Wistar rats. Unknown, however, is whether the anxiolytic-like effects of fatty acids provide a natural mechanism against anxiety in young offspring. The present study assessed the anxiolytic-like effect of a mixture of lauric acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, elaidic acid, and linoleic acid in Wistar rats on postnatal day 28. Infant rats were subjected to the elevated plus maze, defensive burying test, and locomotor activity test. Diazepam was used as a reference anxiolytic drug. A group that was pretreated with picrotoxin was used to explore the participation of

Topics: Animals; Anti-Anxiety Agents; Anxiety Disorders; Diazepam; Fatty Acids; Fatty Acids, Monounsaturated; Humans; Lauric Acids; Linoleic Acid; Maze Learning; Motor Activity; Myristic Acid; Oleic Acid; Oleic Acids; Palmitic Acid; Rats; Receptors, GABA-A; Stearic Acids

Lipase was used to hydrolyse the lard, and four pork flavours (PFs) were prepared through Maillard reaction using different enzyme-treated lards. Volatile compounds and free fatty acids of lard, and volatile compounds of PFs were analysed by GC-MS. The results showed that the total free fatty acids (FFAs) were 89.40%, 85.80% and 89.92% lower in lard control compared with three different enzyme-treated lards (S1, S2 and S3), respectively. Analysis of volatiles of PFs indicated that the effect of lard with moderate lipase treatment on Maillard reaction was more prominent than that of others. The results of descriptive sensory analysis confirmed that PF3 from S3 had the strongest porky, meaty and odour-tenacity. The relationship between FFAs in lard and volatile compounds and sensory attributes of the PFs showed that 9c-C18:1 oleic acid, 9t-C18:1 elaidic acid, 10c-C17:1 heptadecenoic acid, 9c,12c-C18:2 linoleic, C18:0 stearic and 9c-C16:1 palmitoleic might be pork flavour precursors which were present at highest concentrations in lipase MER "Amano" pretreated lard.

Topics: Adult; Animals; Dietary Fats; Fatty Acids, Monounsaturated; Fatty Acids, Nonesterified; Female; Food Handling; Gas Chromatography-Mass Spectrometry; Humans; Hydrolysis; Least-Squares Analysis; Linoleic Acid; Lipase; Maillard Reaction; Male; Middle Aged; Oleic Acid; Oleic Acids; Red Meat; Stearic Acids; Swine; Taste; Volatile Organic Compounds; Young Adult

Aedes aegypti and Aedes albopictus and Culex pipiens pallens mosquitoes transmit dengue fever and West Nile virus diseases, respectively. This study was conducted to determine the toxicity and mechanism of action of four flavonoids and two fatty acids from Millettia pinnata (Fabaceae) seed as well as six pure fatty acids and four fatty acid esters toward third instar larvae from insecticide-susceptible C. pipiens pallens and A. aegypti as well as wild A. albopictus. Efficacy of 12 experimental liquid formulations containing M. pinnata seed methanol extract and hydrodistillate (0.5-10.0% liquids) was also assessed.. The contact toxicities of all compounds and 12 formulations were compared with those of two larvicides, temephos and fenthion and the commercial temephos 200 g/L emulsifiable concentrate (EC). The possible mode of larvicidal action of the constituents was elucidated using biochemical methods. Larval mortality and cAMP level were analyzed by the Bonferroni multiple-comparison method.. Potent toxicity was produced by karanjin, oleic acid, karanjachromene, linoleic acid, linolenic acid, pongamol, pongarotene, and elaidic acid toward C. pipiens pallens larvae (24 h LC50, 14.61-28.22 mg/L) and A. aegypti larvae (16.13-37.61 mg/L). Against wild A. albopictus larvae, oleic acid (LC50, 18.79 mg/L) and karanjin (35.26 mg/L) exhibited potent toxicity. All constituents were less toxic than either temephos or fenthion. Structure-activity relationship indicates that the degree of saturation, the side chain length, and the geometric isomerism of fatty acids appear to play a role in determining the fatty acid toxicity. Acetylcholinesterase (AChE) is the main site of action of the flavonoids, oleic acid, and palmitic acid. The mechanism of larvicidal action of elaidic acid, arachidic acid, and behenic acid might be due to interference with the octopaminergic system. Linoleic acid and linolenic acid might act on both AChE and octopaminergic receptor. M. pinnata seed extract or hydrodistillate applied as 10% liquid provided 100% mortality toward the three mosquito species larvae and the efficacy of the liquids was comparable to that of temephos 200 g/L EC.. Further studies will warrant possible applications of M. pinnata seed-derived products as potential larvicides for the control of mosquito populations.

Topics: alpha-Linolenic Acid; Animals; Benzofurans; Benzopyrans; Biological Assay; Culicidae; Cyclic AMP; Fatty Acids; Flavonoids; Gas Chromatography-Mass Spectrometry; Heterocyclic Compounds, 4 or More Rings; Insect Vectors; Larva; Lethal Dose 50; Linoleic Acid; Millettia; Mosquito Control; Oleic Acid; Oleic Acids; Plant Extracts; Seeds; Species Specificity; Structure-Activity Relationship

The fatty acid composition of the underutilised Cassia abbreviata seed oil was determined using gas chromatographic methods. C. abbreviata seeds yielded 9.53% of yellowish-green oil consisting mainly of oleic acid (37.8%), palmitic acid (26.5%), linoleic acid (26.7%), stearic acid (4.1%) and elaidic acid (2.1%). The oil was solid at room temperature, had a saponification value of 376.16 mg KOH/g and an iodine value of 26.48 g I2/100g oil. The fatty acid composition and saponification value of the C. abbreviata seed oil suggest that it may find application in both cosmetic and pharmaceutical natural product formulations.

Topics: Cassia; Fatty Acids; Linoleic Acid; Oleic Acid; Oleic Acids; Palmitic Acid; Plant Oils; Seeds; Stearic Acids

Numerous reports have shown that a diet containing large amounts of trans fatty acids (TFAs) is a major risk factor for metabolic disorders. Although recent studies have shown that TFAs promote intestinal inflammation, the underlying mechanisms are unknown. In this study, we examined the effects of dietary fat containing TFAs on dextran sodium sulphate (DSS)-induced colitis. C57 BL/6 mice were fed a diet containing 1·3% TFAs (mainly C16:1, C18:1, C18:2, C20:1, C20:2 and C22:1), and then colitis was induced with 1·5% DSS. Colonic damage was assessed, and the mRNA levels of proinflammatory cytokines and major regulators of T cell differentiation were measured. The TFA diet reduced survival and exacerbated histological damage in mice administered DSS compared with those fed a TFA-free diet. The TFA diet significantly elevated interleukin (IL)-6, IL-12p40, IL-23p19 and retinoic acid-related orphan receptor (ROR)γt mRNA levels in the colons of DSS-treated animals. Moreover, IL-17A mRNA levels were elevated significantly by the TFA diet, with or without DSS treatment. We also examined the expression of proinflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and peritoneal macrophages. These cells were exposed to TFAs (linoelaidic acid or elaidic acid) with or without LPS and the mRNA levels of various cytokines were measured. IL-23p19 mRNA levels were increased significantly by TFAs in the absence of LPS. Cytokine expression was also higher in LPS-stimulated cells exposed to TFAs than in unexposed LPS-stimulated cells. Collectively, our results suggest that TFAs exacerbate colonic inflammation by promoting Th17 polarization and by up-regulating the expression of proinflammatory cytokines in the inflamed colonic mucosa.

Topics: Animals; Cell Differentiation; Cell Line; Colitis; Cytokines; Dextran Sulfate; Female; Inflammation; Interleukin-12 Subunit p40; Interleukin-17; Interleukin-23 Subunit p19; Interleukin-6; Linoleic Acid; Lipopolysaccharides; Macrophages; Mice; Mice, Inbred C57BL; Nuclear Receptor Subfamily 1, Group F, Member 3; Oleic Acid; Oleic Acids; RNA, Messenger; Th17 Cells; Trans Fatty Acids; Up-Regulation

Trans fatty acids (TFA) have been considered as an independent risk factor of coronary heart disease, sudden death and insulin-resistance, and different TFA isomers may have different effects on the progression of cardiovascular diseases such as atherosclerosis. The aim of the study was to investigate the effects of two major TFA, elaidic acid and linolelaidic acid which have the same number of carbons but a different number and configuration of trans bonds, on the proliferation of human umbilical vein smooth muscle cells (HUVSMC). Methyl thiazolyl tetrazolium and flow cytometry assays showed that the cell proliferation rose to 115.37 ± 0.39 and 117.5 ± 0.57 % and the cell number in the S phase of the cell cycle reached 27.7 ± 0.7 and 25.8 ± 2.8 % when treated with 50 μM elaidic acid and 20 μM linolelaidic acid, respectively. Quantitative real-time reverse transcriptase-polymerase chain reaction and Western blotting analyses showed that the two TFA increased the mRNA and protein expression levels of PCNA, CDK2 and Cyclin E in HUVSMC. Moreover, gas chromatography analysis showed that the total PUFA level of HUVSMC was lower after treatment with the two TFA, especially n-3 PUFA. These results suggested that linolelaidic acid exhibited a stronger proliferative effect on HUVSMC than elaidic acid, and regulation of CDK2 and Cyclin E may be important for the effect of the TFA on atherosclerosis.

Topics: Cell Cycle; Cell Proliferation; Cyclin E; Cyclin-Dependent Kinase 2; Fatty Acids; Gene Expression Regulation; Humans; Linoleic Acid; Myocytes, Smooth Muscle; Oleic Acid; Oleic Acids; Proliferating Cell Nuclear Antigen; RNA, Messenger; Umbilical Veins

Epidemiological data have shown an association of the intake of industrial produced trans fatty acids (TFA) and sudden cardiac death. The present study examines the impact of elaidic acid (t18:1n-9) and linoelaidic acid (t18:2n-6) on the human aortic endothelial cell functional response. Trans fatty acids predominately incorporated into the phospholipid component while only a minute fraction of the total fatty acids (FA) incorporated into triacylglycerol. Trans fatty acids incorporated into the plasma membranes at the expense of the saturated-FA, stearic, palmitic, and to a lesser extent, myristic acid. Both t18:1n-9 and t18:2n-6 induced a pro-inflammatory response by elevating surface expression of intercellular adhesion molecule-1 (ICAM-1). Neither oleic nor linoleic evoked a pro-inflammatory phenotype under the maximal 50 µM treatments. Both TFA and stearic acid increased phosphorylation of the ICAM-1 transcriptional regulator, nuclear factor-κβ (NF-κβ), while oleic and linoleic acids did not appear to alter the phosphorylation status. Elaidic acid minimally affected endothelial cell growth, whereas linoelaidic acid completely inhibited growth at 100 µM and imparted limited cytotoxicity up to 300 µM. Stearic acid induced cytotoxicity at concentrations above 75 µM, while oleic and linoleic acids evoked gradual dose-dependent growth inhibition with cytotoxicity occurring only at linoleic acid concentrations greater than 200 µM. In conclusion, t18:1n-9 and t18:2n-6 fatty acids effectively incorporated into the phospholipid component of endothelial cells and subsequently induce a pro-inflammatory phenotype.

Topics: Cell Membrane; Cell Proliferation; Cells, Cultured; Endothelial Cells; Fatty Acids; Linoleic Acid; Oleic Acid; Oleic Acids; Stearic Acids; Trans Fatty Acids; Triglycerides

To investigate the relationship between chemical structure and physiological effect, the efficacy and the molecular mechanisms involved in the reduction of body weight by C18 fatty acids (stearic, elaidic, oleic, linoleic and 2-hydroxyoleic acids (2-OHOA)).. Ad libitum fed, lean Wistar Kyoto rats treated orally with up to 600 mg kg(-1) of the fatty acids or vehicle every 12 h for 7 days. Besides, starved rats and rats pairfed to the 2-OHOA-treated group served as additional controls under restricted feeding conditions.. Body weight, food intake, weight of various fat depots, plasma leptin, hypothalamic neuropeptides, uncoupling proteins (UCP) in white (WAT) and brown adipose tissue (BAT) and phosphorylation level of cyclic AMP (cAMP) response element-binding protein (CREB) in WAT.. Only treatment with oleic acid and 2-OHOA induced body weight loss (3.3 and 11.4%, respectively) through reduction of adipose fat mass. Food intake in these rats was lower, although hypothalamic neuropeptide and plasma leptin levels indicated a rise in orexigenic status. Rats pairfed to the 2-hydroxyoleic group only lost 6.3% body weight. UCP1 expression and phosphorylation of CREB was drastically increased in WAT, but not BAT of 2-OHOA-treated rats, whereas no UCP1 expression could be detected in WAT of rats treated with oleic acid.. Both cis-configured monounsaturated C18 fatty acids (oleic acid and 2-OHOA) reduce body weight, but the introduction of a hydroxyl group in position 2 drastically increases loss of adipose tissue mass. The novel molecular mechanism unique to 2-hydroxyoleic, but not oleic acid, implies induction of UCP1 expression in WAT by the cAMP/PKA pathway-dependent transcription factor CREB, most probably as part of a transdifferentiation process accompanied by enhanced energy expenditure.

Topics: Adipose Tissue; Animals; Body Weight; Fatty Acids; Feeding Behavior; Immunoblotting; Leptin; Linoleic Acid; Neuropeptides; Oleic Acid; Oleic Acids; Random Allocation; Rats; Rats, Wistar; Reverse Transcriptase Polymerase Chain Reaction; Stearic Acids; Structure-Activity Relationship

Transient receptor potential vanilloid (TRPV) channels are polymodal detectors of multiple environmental factors, including temperature, pH, and pressure. Inflammatory mediators enhance TRPV function through multiple signaling pathways. The lipoxygenase and epoxygenase products of arachidonic acid (AA) metabolism have been shown to directly activate TRPV1 and TRPV4, respectively. TRPV3 is a thermosensitive channel with an intermediate temperature threshold of 31-39 degrees C. We have previously shown that TRPV3 is activated by 2-aminoethoxydiphenyl borate (2APB). Here we show that AA and other unsaturated fatty acids directly potentiate 2APB-induced responses of TRPV3 expressed in HEK293 cells, Xenopus oocytes, and mouse keratinocytes. The AA-induced potentiation is observed in intracellular Ca2+ measurement, whole-cell and two-electrode voltage clamp studies, as well as single channel recordings of excised inside-out and outside-out patches. The fatty acid-induced potentiation is not blocked by inhibitors of protein kinase C and thus differs from that induced by the kinase. The potentiation does not require AA metabolism but is rather mimicked by non-metabolizable analogs of AA. These results suggest a novel mechanism regulating the TRPV3 response to inflammation, which differs from TRPV1 and TRPV4, and involves a direct action of free fatty acids on the channel.

Topics: Animals; Arachidonic Acid; Boron Compounds; Calcium; Cell Line; Cells, Cultured; Electrophysiology; Enzyme Activation; Fatty Acids, Unsaturated; Humans; Inflammation; Keratinocytes; Kidney; Linoleic Acid; Mice; Oleic Acid; Oleic Acids; Oocytes; Patch-Clamp Techniques; Protein Kinase C; Signal Transduction; TRPV Cation Channels; Xenopus Proteins

This study was conducted to determine the secretion rate and composition of lipoproteins secreted by HepG2 cells as influenced by the type of fatty acid present in the incubation medium. Cells were preincubated for 24 h with palmitic, oleic, elaidic, linoleic or conjugated linoleic acid (CLA), and the lipoproteins secreted during a subsequent incubation period of 24 h were collected for analysis. The secretion rate of apolipoprotein B-100 (apoB) was significantly greater in HepG2 cells preincubated with elaidic acid compared with those preincubated with palmitic or oleic acid; apoB secretion was greater in cells preincubated with CLA compared with those preincubated with linoleic acid. The lipid composition of secreted lipoproteins was also influenced by fatty acid treatment, resulting in significantly smaller lipoprotein particles secreted by cells preincubated with elaidic acid and CLA compared with those secreted by cells treated with oleic acid and linoleic acid, respectively. Our results are relevant to human metabolism for the following reasons: (1) the size of plasma low-density lipoproteins (LDLs) is determined, at least in part, by the composition of apoB-containing lipoproteins secreted by the liver; (2) small plasma LDL particles are associated with an increased risk of coronary heart disease; and (3) specific dietary fatty acids can affect the composition and size of plasma LDLs, thereby imparting a relative atherogenicity to plasma LDLs independent of LDL cholesterol concentration. The present study therefore suggests that elaidic acid and CLA promote the hepatic secretion of small apoB-containing lipoproteins, which could lead to an increased production of small plasma LDL particles.

Topics: Apolipoprotein B-100; Apolipoproteins B; Carcinoma, Hepatocellular; Humans; Linoleic Acid; Linoleic Acids, Conjugated; Lipids; Lipoproteins; Liver; Liver Neoplasms; Oleic Acid; Oleic Acids; Particle Size; Trans Fatty Acids; Tumor Cells, Cultured

The present study was designed to investigate the hypothesis that trans fatty acids can induce apoptosis of human umbilical vein endothelial cells (HUVEC). To test this hypothesis apoptosis was measured in HUVEC treated with 0.1, 1.0 or 5.0 mM trans elaidic acid (t-18:1) or linoelaidic acid (t,t-18:2) for 24 hours. For the detection of apoptosis, TdT-mediated dUTP nick end labelling assay (TUNEL), cell binding of annexin V and propidium iodide uptake were measured. Active Caspase-3 and cleaved PARP (poly-ADP-ribose polymerase) were also measured in the cell lysate. Moreover, cellular ability to produce ROS (reactive oxygen species) was measured by DCF fluorescence Both acids studied induce both early (annexin-positive cells) and late stages of apoptosis (cells stained by propidium iodide) in a dose-dependent manner. Also the appearance of TUNEL-positive cells was induced by both trans fatty acids tested, in a dose dependent manner. Both trans acids induce apoptosis through their effect on Caspase-3 activity and on intracellular ROS production. It is worth emphasising that linoelaidic acid proved to be a more potent inducer of apoptosis and ROS production in endothelial cells than elaidic acid. The present studies suggest that trans fatty acids may play a role in damaging and death of vascular endothelial cells in atherosclerosis.

Topics: Apoptosis; Caspase 3; Cells, Cultured; Dose-Response Relationship, Drug; Endothelial Cells; Humans; Linoleic Acid; Oleic Acid; Oleic Acids; Poly(ADP-ribose) Polymerases; Reactive Oxygen Species; Trans Fatty Acids

Fatty acids have both stimulatory and inhibitory effects on insulin secretion. Long-term exposure to fatty acids results in impaired insulin secretion whilst acute exposure has generally been found to enhance insulin release. However, there are conflicting data in the literature as to the relative efficacy of various fatty acids and on the glucose dependency of the stimulatory effect. Moreover, there is little information on the responses of human islets in vitro to fatty acids. We have therefore studied the acute effects of a range of fatty acids on insulin secretion from rat and human islets of Langerhans at different glucose concentrations. Fatty acids (0.5 mM) acutely stimulated insulin release from rat islets of Langerhans in static incubations in a glucose-dependent manner. The greatest effect was seen at high glucose concentration (16.7 mM) and little or no response was elicited at 3.3 or 8.7 mM glucose. Long-chain fatty acids (palmitate and stearate) were more effective than medium-chain (octanoate). Saturated fatty acids (palmitate, stearate) were more effective than unsaturated (palmitoleate, linoleate, elaidate). Stimulation of insulin secretion by fatty acids was also studied in perifused rat islets. No effects were observed at 3.3 mM glucose but fatty acids markedly potentiated the effect of 16.7 mM glucose. The combination of fatty acid plus glucose was less effective when islets had been first challenged with glucose alone. The insulin secretory responses to fatty acids of human islets in static incubations were similar to those of rat islets. In order to examine whether the responses to glucose and to fatty acids could be varied independently we used an animal model in which lactating rats are fed a low-protein diet during early lactation. Islets from rats whose mothers had been malnourished during lactation were still able to respond effectively to fatty acids despite a lowered secretory response to glucose. These data emphasise the complex interrelationships between nutrients in the control of insulin release and support the view that fatty acids play an important role in glucose homeostasis during undernutrition.

Topics: Animals; Caprylates; Cells, Cultured; Fatty Acids; Fatty Acids, Monounsaturated; Female; Glucose; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Lactation; Linoleic Acid; Models, Animal; Nutrition Disorders; Oleic Acid; Oleic Acids; Palmitates; Rats; Rats, Wistar; Stearates; Stimulation, Chemical

We used single-channel recording techniques to identify and characterize a large-conductance, Ca(2+)-independent K+ channel in the colonic secretory cell line T84. In symmetric potassium gluconate, this channel had a linear current-voltage relationship with a single-channel conductance of 161 pS. Channel open probability (Po) was increased at depolarizing potentials. Partial substitution of bath K+ with Na+ indicated a permeability ratio of K+ to Na+ of 25:1. Channel Po was reduced by extracellular Ba2+. Event-duration analysis suggested a linear kinetic model for channel gating having a single open state and three closed states: C3<-->C2<-->C1<-->O. Arachidonic acid (AA) increased the Po of the channel, with an apparent stimulatory constant (Ks) of 1.39 microM. Neither channel open time (O) nor the fast closed time (C1) was affected by AA. In contrast, AA dramatically reduced mean closed time by decreasing both C3 and C2. The cis-unsaturated fatty acid linoleate increased Po also, whereas the saturated fatty acid myristate and the trans-unsaturated fatty acid elaidate did not affect Po. This channel is activated also by negative pressure applied to the pipette during inside-out recording. Thus we determined the effect of the stretch-activated channel blockers amiloride and Gd3+ on the K+ channel after activation by AA. Amiloride (2 mM) on the extracellular side reduced single-channel amplitude in a voltage-dependent manner, whereas Gd3+ (100 microM) had no effect on channel activity. Activation of this K+ channel may be important during stimulation of Cl- secretion by agonists that use AA as a second messenger (e.g., vasoactive intestinal polypeptide, adenosine) or during the volume regulatory response to cell swelling.

Topics: Amiloride; Arachidonic Acid; Cell Membrane; Cell Membrane Permeability; Colon; Gadolinium; Humans; Intestinal Mucosa; Ion Channel Gating; Linoleic Acid; Membrane Potentials; Oleic Acid; Oleic Acids; Patch-Clamp Techniques; Potassium; Potassium Channels; Probability; Second Messenger Systems; Sodium

The regulation of plasma lecithin:cholesterol acyltransferase (LCAT) expression is not well understood. Although oleic acid increases both the secretion of triglycerides and LCAT by primary rat hepatocytes, the effect of other fatty acids (FA) on LCAT secretion is not known. This study was designed to examine the effect of FA on the hepatic secretion of LCAT, triglyceride and apolipoprotein A-1 (apoA-1). Primary rat hepatocytes were incubated with serum-free medium, supplemented with individual FA (0-1 mmol/L) for 22-24 h. Preliminary studies indicated a linear secretion of LCAT up to 24 h in both control and FA-treated cells. When hepatocytes were incubated with 1 mmol/L FA, the LCAT secretion increased 50-100% (P < 0.01) in the presence of the 18-carbon FA (stearic, oleic, elaidic and linoleic acids), whereas the presence of butyric, lauric and palmitic acids had no significant effect. LCAT secretion decreased (P < 0.01) in the presence of docosahexaenoic acid (DHA). All FA (except DHA) significantly enhanced triglyceride secretion; however, only the 18 carbon FA significantly stimulated the synthesis and secretion of apoA-1 and secretion of LCAT. The secretion of LCAT correlated with apoA-1 secretion (r = 0.88, P = 0.004) but not with triglyceride secretion (r = 0.55, P = 0.12). Treatment with oleic acid resulted in a 1.5-fold increase in hepatocyte LCAT mRNA accumulation, whereas butyrate and palmitate had no effect. These data indicate that FA that promote the apparent synthesis and secretion of apoA-1 also stimulate the secretion of LCAT in vitro, suggesting a coordinate regulatory mechanism for apoA-1 and LCAT expression.

Topics: Animals; Apolipoprotein A-I; Cells, Cultured; Dose-Response Relationship, Drug; Fatty Acids; Gene Expression; Linoleic Acid; Liver; Male; Oleic Acid; Oleic Acids; Phosphatidylcholine-Sterol O-Acyltransferase; Rats; Rats, Sprague-Dawley; RNA, Messenger; Stearic Acids; Triglycerides

The incorporation of [14C]elaidic acid (trans18:1(n-9)) in phosphatidylcholine and phosphatidylethanolamine molecular species in isolated rat liver cells has been studied, and the results compared with the incorporation, previously published (B. Woldseth et al. Biochim Biophys Acta 1993; 1167: 296-302), of [14C]palmitic acid (16:0) and [14C]stearic acid (18:0) and with that of [14C]oleic acid (cis18:1(n-9)). The pattern of incorporation in phospholipid molecular species is similar to that of [14C]stearic acid and different from that of [14C]palmitic acid. In phosphatidylcholine [14C]trans18:1-18:2 and [14C]trans18:1-20:4 were the most abundant species, and in phosphatidylethanolamine [14C]trans18:1-20:4 was the predominant species. With increasing concentration of [14C]elaidic acid increasing amounts of [14C]trans18:1-[14C]trans18:1 were found. The total incorporation in phospholipids was less than that of [14C]stearic acid, but more than that of [14C]palmitic acid. The distribution in percent of [14C]elaidic acid in phospholipid classes was 8.8% in phosphatidylinositol, 1.8% in phosphatidylserine, 59.1% in phosphatidylcholine and 30.3% in phosphatidylethanolamine with 0.1 mmol l-1 substrate concentration. More [14C]elaidic acid than [14C]palmitic acid or [14C]stearic acid was oxidized. The incorporation in phospholipids of [14C]elaidic acid was very different from that of [14C]oleic acid. The main species with [14C]oleic acid were 16:0-[14C]cis18:1 in phosphatidylcholine, and [14C]cis18:1-20:4 in phosphatidylethanolamine. In some experiments [14C]18:2(n-6) was incubated together with unlabelled elaidic or unlabelled trans-vaccenic acid (trans18:1(n-7)). In these experiments, more trans18:1-18:2 was formed from elaidic acid than from trans-vaccenic acid, especially in phosphatidylethanolamine.

Topics: Animals; Carbon Radioisotopes; Chromatography, Gas; Esterification; Fatty Acids, Monounsaturated; Linoleic Acid; Liver; Male; Oleic Acid; Oleic Acids; Oxidation-Reduction; Palmitic Acid; Phosphatidylcholines; Phosphatidylethanolamines; Rats; Rats, Wistar; Stearic Acids

Following the demonstration of the antimalarial effect of the long chain saturated alcohol n-hentriacontanol ((CH2)29CH2OH), isolated from the Bolivian endemic solanaceous plant Cuatresia sp., we have tested the effect of the C18 fatty acids oleic, elaidic, linoleic, and linoleic on malaria parasites. These fatty acids inhibited the parasitemic development in mice infected with Plasmodium vinckei petteri or with Plasmodium yoelii nigeriensis in a 4-day suppressive test. To gain a deeper discernment of the antimalarial mode of action, the effects of these compounds were evaluated on Plasmodium falciparum growth in culture. Whereas n-hentriacontanol did not show any inhibition of this parasite, on the contrary, the C18 acids displayed a considerably inhibitory activity at < or = 200 micrograms/ml both in intact infected cells and in free parasites. In order to understand the mechanism of their antimalarial action, several tests were performed. No hemolysis of infected cells could be observed up to 500 microgram/ml. No effect on the lipid peroxidation, ATP levels, transport through the parasite-induced permeability pathways, or on the phagocytosis of the infected cells could be observed. The cytotoxic effect of the fatty acids was very rapid: full inhibition of nucleic acids and protein syntheses was observed in less than 30 min. This inhibition was not relieved by the addition of deferrioxamine or FeCl3, indicating that fatty acids (FA) do not act by facilitating the transport of iron. Inhibition was relieved in neither the presence of orotic acid or its methyl ester, indicating that FA do not act at the mitochondrial level of pyrimidine synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: alpha-Linolenic Acid; Animals; Antimalarials; Fatty Acids, Nonesterified; Linoleic Acid; Linoleic Acids; Malaria; Male; Mice; Oleic Acid; Oleic Acids; Parasitemia; Plasmodium; Plasmodium falciparum; Plasmodium yoelii; Structure-Activity Relationship

Trans isomeric fatty acids disturb the metabolism of essential polyunsaturated fatty acids in animals and in premature infants. We assessed whether similar effects may also occur in healthy children. Plasma phospholipid fatty acid composition was analysed in 53 apparently healthy children aged 1-15 years (mean 7.5 years). Trans fatty acids were found in all samples and contributed 1.78 +/- 0.10% (w/w, mean +/- SEM). There was no relation of the major trans isomer octadecenoic acid and of total trans fatty acids to the precursor essential fatty acid linoleic acid. In contrast, we found significant inverse correlations of trans octadecenoic acid and total trans isomers to the principal n-6 metabolite arachidonic acid as well as to the sum of all n-6 metabolites. Furthermore, there was an inverse correlation of total trans fatty acids to the ratio of arachidonic to linoleic acid, an indirect indicator of linoleic acid conversion. These findings are compatible with inhibition of arachidonic acid biosynthesis by trans fatty acids. Since the availability of long-chain polyunsaturated fatty acids, including arachidonic acid, is of essential importance for tissue growth and development, these findings question the safety of high dietary trans fatty acid intakes in childhood.

Topics: Adolescent; Arachidonic Acid; Child; Child, Preschool; Dietary Fats; Fatty Acids; Female; Humans; Infant; Linoleic Acid; Linoleic Acids; Male; Oleic Acid; Oleic Acids; Phospholipids; Reference Values; Stereoisomerism

When rats were fed elaidic (trans-9 18:1) acid at a high load in diets that were otherwise marginally or almost completely deficient in linoleic (cis-9,cis-12 18:2) acid, elaidic acid was desaturated to cis-5,trans-9 18:2 acid. This polymethylene-interrupted acid was then incorporated into most phospholipids from rat mitochondria, cardiolipin being an exception. Its level of esterification in phospholipids followed the increasing order: phosphatidylethanolamine < phosphatidylcholine < phosphatidylinositol (PI). The content of cis-5,trans-9 18:2 acid decreased in organs in the order liver > kidney > heart. The levels of cis-5,trans-9 18:2 acid increased in mitochondria phospholipids as the level of linoleic acid was lowered in the diet. In liver mitochondria PI, it reached 16% of total fatty acids. After hydrolysis of liver mitochondria PI with Naja naja phospholipase A2, we observed that elaidic acid was essentially esterified to position 1 at the expense of saturated acids, whereas cis-5,trans-9 18:2 acid was exclusively esterified to position 2, along with 20:3n-9 and 20:4n-6 acids. As a consequence, the sums of saturated and trans-9 18:1 acids on the one hand, and of 20:3n-9, 20:4n-6, and cis-5,trans-9 18:2 acids on the other hand, remained fairly constant in liver mitochondria PI (ca. 55 and 30%, respectively). Because trans-9 18:1 and cis-5,trans-9 18:2 acids differ only by the cis-5 ethylenic bond, which is also present in 20:3n-9 and 20:4n-6 acids, this distribution pattern indicates that the cis-5 double bond, rather than any other ethylenic bond, may be of major structural importance for channeling fatty acids to position 2 of PI.

Topics: Acylation; Animals; Cardiolipins; Dietary Fats; Esterification; Ethylenes; Fatty Acid Desaturases; Kidney; Linoleic Acid; Linoleic Acids; Male; Mitochondria; Mitochondria, Heart; Mitochondria, Liver; Oleic Acid; Oleic Acids; Phosphatidylcholines; Phosphatidylethanolamines; Phosphatidylinositols; Phospholipases A; Phospholipases A2; Rats; Rats, Wistar

Differences in the positional incorporation of 9-trans[1-(14)C] octadecenoic (elaidic) and 9-trans,12-trans[1-(14)C] octadecadienoic (linoelaidic) acids in fetal lecithin of rats were demonstrated. On the 20th day of gestation, a 14C-labeled albumin complex of elaidic or linoelaidic acid was injected into the jugular vein of pregnant rats. For comparative purposes, 9-cis[1-(14)C] octadecenoic (oleic) or 9-cis,12-cis[1-(14)C] octadecadienoic (linoleic acid) was injected into the maternal circulation of rats. Animals were killed 6 hr later. Distribution of label in total lipids and phospholipids (PL) of fetal issue was measured by TLC. Irrespective of the label, the highest percentage of total radioactivity was associated with PL-59 to 67%. Within PL, the major portion of radioactivity was found in choline phosphoglycerides (CPG)-53 to 67%, and in ethanolamine phosphoglycerides (EPG)-18 to 33%. While linoelaidic acid was predominantly esterified in the 2-position of CPG, elaidic acid was nearly equally distributed between positions 1 and 2 of lecithin. Distribution of radioactivity within fatty acid methyl esters (FAME) of CPG measured by radio-GLC suggested that oleic and possibly linoleic acids may be converted to nervonic and arachidonic acid, respectively, in the rat by the 20th day of gestation. Following injection of elaidate, radioacivity of FAME was distributed between palmitate and elaidic acid indicating that rat fetal tissue may metabolize elaidic acid via beta-oxidation. In contrast, following injection of linoelaidate, radioactivity of FAME was primarily associated with tt-18:2, suggesting little biotransformation to other fatty acids by fetal tissues.

Topics: Animals; Fatty Acids; Fatty Acids, Unsaturated; Female; Fetus; Isomerism; Linoleic Acid; Linoleic Acids; Oleic Acid; Oleic Acids; Phosphatidylcholines; Phospholipases A; Phospholipids; Pregnancy; Rats

Placental transport of 9-trans [1-14C] octadecenoic (elaidic) and 9-trans,12-trans [1-14C] octadecadienoic (linoelaidic) acids was demonstrated in rats. On the 18th day of gestation, a 14C-labeled albumin complex of elaidic or linoelaidic acid was injected into the jugular vein of pregnant rats. For comparison, 9-cis [1-14C] octadecenoic (oleic) or 9-cis,12-cis [1-14C] octadecadienoic (linoleic) acid also was injected into the maternal circulation of rats. All animals were sacrificed 1 hr following injection. Lipid composition and distribution of label were determined in maternal plasma, placental and fetal tissues. Differences in specific activities of plasma, placental and fetal total lipids indicated a decreasing concentration gradient for both cis and trans isomers of octadecenoic and octadecadienoic acids. Distribution of radioactivity in various lipid components was determined by thin layer chromatography. Irrespective of the label, the highest percentage of total radioactivity was carried by triglycerides (TG) in maternal plasma (approximately 60-80%), and was incorporated mainly in phospholipids (PL) of fetal tissue (approximately 50-60%). A nearly equal distribution of the label was found between PL and TG of placental lipids (approximately 40%). Radioactivity of fatty acid methyl esters (FAME) determined by radio-gas liquid chromatography indicated that after injection of linoelaidate, radioactivity of maternal plasma, placental and fetal tissue FAME was associated only with t,t-18:2. Following injection of elaidate, all the radioactivity in placental FAME was associated with t-18:1; however, in fetal tissues, the label was distributed between 16:0 and t-18:1. These findings suggest that, in contrast to linoelaidic acid, rat fetal tissues can metabolize elaidic acid via beta oxidation to form acetyl CoA and palmitic acid.

Topics: Animals; Brain; Fatty Acids, Unsaturated; Female; Fetus; Linoleic Acid; Lipid Metabolism; Maternal-Fetal Exchange; Oleic Acid; Oleic Acids; Placenta; Pregnancy; Rats; Stereoisomerism; Structure-Activity Relationship