[Short term comparative study of effects of n-9 trans-docosenoic (brassidic) acid and n-9, cis-docosenoic (erucic) acid on the cardiac lipids of weanling rats]. / Effets comparés, à très court terme, des acides n-9, trans-docosénoïque (brassidique) et n-9, cis-docosénoïque (érucique) sur les lipides cardiaques du rat sevré

Cardiac lipids (triglycerides and phospholipids) of weanling rats fed diets containing 15% by weight of rapeseed oil (RSO), hydrogenated rapeseed oil (HRSO), trierucin (TE) or tribassidin (TB) were analyzed after 3 and 7 days of feeding. The amount of C22:1 was made equal in the 4 diets. Trans-isomers of erucic acid found in HRSO and TB do not cause as high an accumulation of lipids and docosenoic acids in the heart as erucic acid. Digestibility of brassidic acid (46%) is lower than that or erucic acid (83%) but even then, the amount of brassidic acid found in cardiac lipids (calculated per gram of absorbed fatty acid) after 7 days of feeding is 10 times less than that of erucic acid. Brassidic acid, like erucic acid, can be converted into shorter monoenes (C20:1 and C18:1) since transC18:1 has been found in cardiac phospholipids of rats fed trans-docosenoic acid as the only source of trans-acid in the diet.

Computerized analysis of food records: role of coding and food composition database.

Reported dietary intake records of 30 subjects (26 men and 4 women) were analysed by three different centres using their own computerized nutrient database systems. The agreement between systems was evaluated by different statistical criteria (the correlation coefficient, the mean difference and the proportion of individuals placed in the same thirds of distribution). Significant differences between the three systems were found in the calculation of alcohol, polyunsaturated fatty acids, saturated fatty acids, linoleic acid, linolenic acid, cholesterol, magnesium, sodium and water. To ascertain the extent of mean differences that could be attributed to the coding process or to the database used, coding forms of each centre were forwarded to the other two centres. Analysis of variance showed that differences in the data obtained by the three systems were mainly due to the food composition database used.

Polyunsaturated fatty acids in tissues of rats fed trielaidin and high or low levels of linolenic acid.

Male and female weanling rats that were born to dams fed a diet low in linolenic acid received diets of 15% lipids by weight containing 45% elaidic acid (as trielaidin) and 8.5% or 0.1% linolenic acid for 10 weeks. Four other groups, in which palmitic or oleic acid replaced elaidic acid in the diet, served as controls. The fatty acid profiles of several lipid classes were determined in adipose tissue, adrenals, testes, heart and brain. Elaidic acid was incorporated into tissue lipids in varying degrees, depending on the organ and on the lipid class. Feeding elaidic acid induced no changes in the polyunsaturated fatty acid (PUFA) profiles of testes lipids but resulted in definite modifications of the PUFA patterns of heart phosphatidylcholine (PC) and phosphatidylethanolamine (PE). In linolenic acid-deprived rats, arachidonic acid was decreased in PC and linoleic acid was increased in both PC and PE; 22:5n-6 was strongly depressed in both PC and PE. In linolenic acid-fed rats, 22:6n-3 was decreased in PC and PE. These changes, on the whole, were more evident in females, and some also were observed in adrenal cholesteryl esters but only slightly in brain phospholipids. The apparent inhibition of the biosynthesis of PUFA induced by dietary elaidic acid appeared to be complex and of greater intensity in the n-6 fatty acid series than in their n-3 homologues.

Separation and quantification of heart and liver phospholipid classes by high-performance liquid chromatography using a new light-scattering detector.

This work describes a one-step separation of rat tissue phospholipid classes by high-performance liquid chromatography (HPLC) using a silica column and a new light-scattering detector (LSD). Complete separation of phosphatidylcholine, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol, phosphatidylserine, sphingomyelin, lysophosphatidylethanolamine, and lysophosphatidylcholine was obtained. Direct quantification was achieved after detector calibration for each phospholipid class. The detector response was shown to be linear within the ranges used. The LSD results agreed well with those obtained by phospholipid phosphorus assay. The present method was applied to rat heart and rat liver phospholipid analysis.

Phospholipid content and fatty acid composition of human heart.

Phospholipid content and fatty acid composition of human heart were determined on 36 biopsy specimens collected during open heart surgery. The main phospholipid classes, phosphatidylcholine (PC), phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), and sphingomyelin (SPH) were separated by HPLC, quantified, and converted to fatty acid methyl esters which were chromatographed on capillary GLC columns. Sex and age (mainly 40-70) of patients had no significant influence on the relative distribution of phospholipid classes and only a slight effect on fatty acid composition. Incorporation of trans 18:1 in phospholipid classes was low. cis and trans octadecenoic isomers seemed to be selectively incorporated, the delta 9 and delta 11 cis or trans isomers being predominant. Human and rat data were compared, and some species differences were noticed. In human PC, palmitic acid is higher and stearic acid much lower than in rat PC. Saturated dimethyl acetals (16:0 and 18:0) in PC and PE were greater for humans. Incorporation of 20:4 n-6 in human PE is higher than in rat PE.

Heart lipidosis induced by short-term feeding of cis- or trans-docosenoic acids in weanling or 7-week-old rats.

Weanling male rats were fed calcium-deprived diets containing 15% lipids, of which half is cis- or trans-docosenoic acid, for 5, 12 or 28 days. Elaidic or oleic acid-fed rats served as controls. After 5 days on diet, the rats fed brassidic acid showed heart triglyceride accumulation, but less than the erucic acid-fed rats. In both groups, the heart triglyceride content decreased with time and returned to normal values after 28 days. When similar diets were fed for 12 days to 7-week-old rats, brassidic acid, on the contrary, induced a greater triglyceride accumulation than erucic acid did.

[Digestive utilization of cis and trans docosenoic acids in the rat: effects of dietary levels of calcium and linoleic acid]. / Utilisation digestive des acides cis et trans docosénoiques chez le rat: influence des apports alimentaires en calcium et en acide linoéique.

Digestibilities of cis and trans docosenoic acids (C 22:11) have been determined in male growing Wistar rats. Eight groups of rats were fed diets with 0.04 or 0.92% calcium and 15% lipids; the latter contained about 46% cis or trans C:22:1, and 1.5 or 28% linoleic acid. Food consumption was recorded and faeces were collected during 9 days. Fecal lipids were extracted in two fractions: soluble (in chloroform), and insoluble; the fatty acids of both fractions were analysed by gas-liquid chromatography. Calcium and, in some cases, Phosphorus, were determined in the soluble fraction. The digestibility of brassidic acid was strongly lowered by the presence of Calcium in the diet (-35 points). This was due to the massive formation, in the gut, of insoluble Calcium complexes (probably Calcium soaps) of brassidic acid. Dietary linoleic acid improves the absorption of brassidic acid (+ 17 points). This effect could result from the lower melting point of the dietary fat (37 degrees C instead of 48 degrees C) and/or from the emulsifying properties of monolinolein in the intestine. The effects of Calcium and of linoleic acid were additives. In the most favourable conditions (no Calcium, 28% linoleic acid), brassidic acid digestibility reached 98%. Erucic acid digestibility was decreased by dietary Calcium, but to a lesser extent than that of brassidic acid (-17 points). Here again, the formation in the gut of Calcium erucate and Calcium-Phosphorus-erucate complexes was responsible of this phenomenon. As a matter of fact, the digestibility of erucic acid reached nearly 100% when no Calcium was added to the diet. The absorption of erucic acid was not improved by dietary linoleic acid.

[Comparison of the mean-term physiological effects of cis or trans docosenoic acids in the rat. I. Digestibility of fatty acids. Effects on growth, organ weights and heart histology]. / Etude comparée des effets physiologiques a moyen terme des acides cis et trans docosénoiques chez le rat. I. Utilisation digestive des acides gras. Effets sur la croissance, le poids des organes, et l'histologie du coeur.

The mean-term physiological effects of brassidic acid (n-9, trans docosenoic acid) and of erucic acid (n-9, cis docosenoic acid) have been compared to those of their C 18 homologues, elaidic and oleic acid, in a 2(3) factorial experiment; the 3 tested factors are: 1) the chain length of the dietary monoenes (C 22:1 vs. C 18:1), 2) the geometrical configuration of their double bond (trans vs. cis) and 3) the dietary level of linoleic acid (30% vs. 1,7% of dietary fatty acids). Wistar weanling rats have been fed for 16 weeks semi-synthetic diets containing 15% of lipids by weight, in which the fatty acids under study (brassidic, erucic elaidic) ranged to 40%. Although caution has been taken to optimize the digestibility of brassidic acid (interesterification of the lipid mixture, reduced level of calcium in the diet, addition of monoglycerides), it remains lower that of erucic acid. However, because of different levels of food consumption, the absorbed amounts of the two isomers are about the same. With a high dietary supply of linoleic acid, the dietary monoenes (C 22:1 or C 18:1), cis or trans) do not induce great changes in the weight gain of the rats, when adjusted to food consumption; linoleic acid subdeficiency lowers this adjusted weight gain, except when the diet contains oleic acid as the only monoene. These effects do not parallel those observed on the absolute growth of the rats. The trans monoenes, and to a lesser extent, erucic acid, induce an increase of liver weight (adjusted to body weight). The light microscopic histological study of the heart does not reveal any difference between the brassidic acid fed-rats and those fed the C 18:1 monoenes (elaidic, oleic). In contrast, erucic acid induces definite lesions of the myocardium. The dietary level of linoleic acid has little influence on the incidence and the severity of the lesions. The effects of these dietary fatty acids on the lipid contents and fatty acid compositions of different organs will be reported in a second paper.

[Comparison of mean-term physiological effects of cis and trans docosenoic acids in the rat. II. Effects on the lipids and fatty acids of plasma, adipose tissue, liver and heart]. / Etude comparée des effets physiologiques a moyen terme des acides cis et trans docosénoiques chez le rat. II. Effets sur les lipides et les acides gras du plasma, du tissu adipeux, du foie et du coeur.

The mean term effects (16 weeks) of brassidic acid (n-9 trans docosenoic acid) and erucic acid (n-9, cis docosenoic acid) on the lipids and fatty acids of different organs in the rat (plasma, adipose tissue, liver, heart) and compared to those of their C 18 homologues, elaidic and oleic acid, in a 2(3) factorial experiment; the three tested factors are: 1) the chain length of the dietary monoenes (C 22:1 vs. C 18:1), 2) the geometrical configuration of their double bond (trans vs. cis) and 3) the dietary levels (30% vs. 1,7% of dietary fatty acids). Experimental details have been reported previously [Astorg and Levillain, 1979]. With a low supply of linoleic acid, brassidic acid, brassidic acid induces a large increase of plasma triacylglycerols (TG), but this can be caused by a slow fat absorption. However, the plasma contents of cis and trans docosenoic acids do not differ greatly. Both docosenoic acids incorporate more into the lipids of heart and adipose tissue than into liver lipids, and, for each organ, more into TG than into phospholipids (PL). In heart and adipose tissue lipids, the percentage of brassidic acid is lower than that of erucic acid. In these 2 organs and in the liver, linoleic acid subdeficiency decreases the incorporation of both C 22:1 isomers into the lipids. Dietary brassidic acid is readily converted to other trans monoenes, mainly elaidic acid, which incorporates into organ lipids. The extent of this chain-shortening may be greater than that of erucic acid (to oleic acid), and this would explain the lower level of brassidic acid found in organ lipids. Last, dietary trans monoenes (brassidic and elaidic acids) induce, as compared to their cis isomers, slight but visible changes in the profile of (n-9) polyunsaturated fatty acids in organ lipids. These results are discussed and related to the fact that brassidic acid does not seem to have the heart pathogenic potency of erucic acid [see part 1 of this paper, Astorg and Levillain, 1979].

[Comparative physiological effects of partially hydrogenated herring and rapeseed oils in the rat. 1. Mean-term effects on growth, organ weights and heart histology]. / Effets physiologiques comparés d'huiles de hareng partiellement hydrogénées et de l'huile de colza chez le rat. I. Effets à moyen terme sur la croissance, le poids des organes et l'histologie du coeur.

Two partially hydrogenated herring oils, containing 15% or 30% of C 22: 1, supplemented or not with linoleic (maize oil), have been fed for 16 weeks to growing rats (15% by weight in the diet), and their effects have been compared to those of peanut oil (controls), and to those of 2 mixtures of rapeseed oil and peanut oil having similar C 22:1 contents (15% and 30%). On the basis of equal amounts of ingested food, the growth of the rats is lower with herring and rapeseed oil than with peanut oil; this phenomenon is emphasized in the case of the non--C 18:2--supplemented herring oils. Herring and rapeseed oils induce an increase of liver particularly with the one having the highest content of trans fatty acids. Heart lesions have been observed in rats feed herring or rapeseed oils, not in the control group. The frequency of these lesions is greater with rapeseed oil (11/13) than with herring oils (11/24). This result suggests that erucic acid (cis delta 13 docosenoic acid) is more pathogenic than at least some of its isomers present in the hydrogenated herring oils (particularly the trans isomers). In the second part of this paper, we report the effects of the tested dietary fats on organ lipids after very short-term (3-7 days) or mean-term (16 weeks) experiments.

[Short term effects of docosenoic acid-containing oils on rat cardiac lipids: colza oil and partially hydrogenated herring oil]. / Effets comparés, à très court terme, d'huiles riches en acide docosénoïque sur les lipides cardiaques du rat: huile de colza et huiles de hareng partiellement hydrogénées

Partially hydrogenated herring oils induce a cardiac lipidosis after a few days of feeding in the Rat. The level of C 22 : 1 in the oil, its chemical structure (erucic acid or isomers) as well as the presence of linoleic acid seem to have an effect upon the intensity of the phenomenon.

Statistical analysis of the size of heart mitochondria in rats fed sunflower oil, primor oil or rapeseed oil.

The size distribution of heart mitochondria was studied in Wistar rats fed for 24 weeks a diet containing sunflower oil, primor oil or rapessed oil. The animals fed rapeseed oil showed larger heart mitochondria than the two other groups. This result could be attributed both to the presence of giant mitochondria and to an increase in size of the whole mitochondrial population. No difference was observed between the sunflower oil group and the primor oil group.

Relationship between lipid parameters and the occurrence and severity of lesions in the heart: a study on rats fed low erucic acid rapeseed oil.

Fifty-six male Wistar SPF rats were fed a diet containing low erucic acid rapeseed (LEAR) oil (15% by weight) as the only source of lipids for 18 wk. Lipid parameters (fatty acid composition and contents of lipid classes) and the occurrence and severity of focal lesions were both determined on the heart of each animal. Four groups were constituted according to the severity of cardiac lesions. Statistical analyses were applied to the data to find a relationship between the lipid parameters and the severity of heart lesions. None of the measured parameters (heart contents of neutral lipids, total phospholipids, phosphatidylcholine, phosphatidylethanolamine, diphosphatidylglycerol, sphingomyelin and fatty acid composition of each phospholipid class) appeared to be related with the grading of the lesions. Therefore, we failed to find a direct support for the assumption that heart lesions, induced by LEAR oil, are mediated by changes in the lipid and/or fatty acid composition of heart membranes. However, this hypothesis can not be discarded.

Quantitative analyses of polar components in frying oils by the iatroscan thin-layer chromatography-flame ionization detection technique.

Frying oils collected in restaurants were fractionated into a polar and a non-polar fraction by the Iatroscan thin-layer chromatography-flame ionization detection (TLC-FID) system on Chromarod S II using hexane-diethyl ether-acetic acid (97:3:1) as the solvent system. The FID responses for Iatroscan analyses of the polar and the non-polar fraction isolated from a frying oil by column chromatography on a 5% hydrated silicic acid were studied at Chromarod load levels ranging from 1 to 16 micrograms, relative to methyl heptadecanoate as the internal standard. The correction factors were relatively constant in the range 10-16 micrograms, but increased in the range 1-5 micrograms. The amount of polar material in ten commercial frying oil samples was quantitated by the Iatroscan TLC-FID technique. Good correlations were found between the results and data obtained by column chromatography and silica gel Sep-Pak cartridges.

beta-Apo-8'-carotenal, but not beta-carotene, is a strong inducer of liver cytochromes P4501A1 and 1A2 in rat.

1. The catalytic activities of several phase I and II xenobiotic-metabolizing enzymes and their immunochemical detection have been investigated in liver microsomes and cytosol of the male rat, which had been fed for 15 days with diets containing 300 mg/kg beta-carotene isomers (all-trans beta-carotene or beta-carotene from Dunaliella salina rich in 9-cis isomer or isomerized beta-carotene), or apocarotenoids as beta-apo-8'-carotenal, ethyl beta-apo-8'-carotenoate and citranaxanthin. 2. Beta-carotene, either all-trans or containing cis isomers, did not induce any significant change in the measured activities. By contrast, beta-apo-8'-carotenal increased the liver content of cytochrome P450, the activity of NADH- and NADPH-cytochrome c reductase, and strongly increased some cytochrome P450-dependent activities, particularly ethoxyresorufin O-deethylase (x158), methoxyresorufin O-demethylase (x22), pentoxy- and benzoxyresorufin O-dealkylases, but did not affect erythromycin N-demethylase nor nitrosodimethylamine N-demethylase activities. Phase II p-nitrophenol- and 4-hydroxy- biphenyl-uridine diphosphoglucuronosyl transferase activities were also increased by beta-apo-8'carotenal. Western blots of microsomal proteins clearly showed the induction of CYP1A1 and 1A2 by beta-apo-8'-carotenal. This induction profile resembles that produced by two other carotenoids: canthaxanthin and astaxanthin. Ethyl beta-apo-8'-carotenoate and citranaxanthin showed similar effects to beta-apo-8'-carotenal but of less intensity. 3. Three carotenoids: beta-apo-8'-carotenal, canthaxanthin and astaxanthin, are inducers of CYP1A1 and 1A2 in the rat. These carotenoids form a new class of inducers of CYP1A, structurally very different from the classical inducers as 3-methylcholanthrene, beta-naphtoflavone or dioxin.