The effects of dietary 9-trans,12-rans-octadecadienoate on composition and fatty acids of rat lungs

Trans fatty acids. 3. Fatty acid composition of the brain and other organs in the newborn piglet

The effects of dietary trans fatty acids on tissue fatty acid composition were studied in newborn piglets delivered from sows fed partially hydrogenated fish oil (PHFO) (28% trans) or partially hydrogenated soybean oil (PHSBO) (36% trans) in comparison with lard (0% trans) from 3 wk of age and through gestation in Experiment 1, or fed PHFO or "fully" hydrogenated fish oil (HFO) (19% trans) in comparison with coconut oil (CF) (0% trans) with two levels, 1 and 2.7%, of dietary linoleic acid from conception through gestation in Experiment 2. The piglets were sampled immediately after delivery, without having access to mothers' milk. Incorporation of trans fatty acids into brain PE (phosphatidylethanolamine) were non-detectable or very low (less than 0.1%). The incorporation of 18:1 trans into heart-PE, liver mitochondria-PE, total plasma lipids and adipose tissue was low, and 20:1 trans was not detected. Dietary trans fatty acids had no consistent effects on the overall fatty acid composition of the different tissue lipids. It is concluded that trans fatty acids from PHFO, HFO and PHSBO have no significant effects on the fatty acid accretion in the fetal piglet.

Trans fatty acids. 1. Growth, fertility, organ weights and nerve histology and conduction velocity in sows and offspring

Effects of dietary trans fatty acids on the pre- and postnatal growth and development in pigs were studied with special emphasis on nervous tissue. In experiment 1, female pigs were fed partially hydrogenated fish oil (PHFO) (28% trans) or soybean oil (PHSBO) (36% trans), in comparison with lard (0% trans) from weaning (3 wk) through the first reproduction cycle (up to 2 yr). In experiment 2, female pigs were fed two fish oils (33 and 19% trans) in comparison with coconut oil (0% trans) in diets with low and high levels of linoleic acid (18:2n-6 cis, cis) from gestation until their offspring were three wk old. Compared with the trans-free fats, the trans-containing fats had no effect on growth and development, feed consumption and utilization or on the weight of the brain, heart, kidneys, liver, lungs or spleen in the adult sows and their offspring. No effects from the experimental fats were found on histology and conduction velocity of the peroneal nerve. An increased number of the sows fed PHFO had fertility problems compared with those fed lard and PHSBO in Expt. 1, but no similar effects were seen in Expt. 2. It is concluded that consumption of trans fatty acids with 18-22 carbon atoms from PHFO and with 18 carbon atoms from PHSBO at levels that were 5 to 12 times higher than those normally consumed by humans had no detrimental effects on female pigs or their offspring during pregnancy and lactation.

Trans fatty acids. 2. Fatty acid composition of the brain and other organs in the mature female pig

Female pigs were fed from three wk of age and up to two years a diet containing partially hydrogenated fish oil (PHFO, 28% trans monoenoic fatty acids), partially hydrogenated soybean oils (PHSBO, 36% trans fatty acids) or lard. No consistent differences were found between PHFO and PHSBO with regard to incorporation of trans fatty acids in organ lipids, but trans incorporations were highly organ-specific. No trans fatty acids were detected in brain phosphatidylethanolamine (PE). The incorporation of monoenoic trans isomers, as a percentage of total cis + trans, in other organs was highest in subcutaneous adipose tissue and liver mitochondria PE, followed by blood lipids with the lowest level in heart PE. The percentage of trans isomers compared with that of dietary lipids was consistently lower for 20:1, compared with 18:1 in organs from PHFO-fed pigs. The only effect of dietary trans fatty acids on the fatty acid pattern of brain PE was an increased level of 22:5n-6. Heart PE and total serum lipids of pigs fed the hydrogenated fats contained higher levels of 18:2n-6, and these lipids of the PHFO-fed group also contained slightly elevated amounts of 20:3n-6, 18:3n-3 and 20:5n-3. Liver mitochondria PE of the PHFO group also contained higher levels of 20:3n-6 and 22:5n-6. Dietary trans fatty acids caused a consistent decrease of saturated fatty acids compensated by increased levels of monoenes.(ABSTRACT TRUNCATED AT 250 WORDS)

Metabolism of cis-12-octadecenoic acid and trans-9,trans-12-octadecadienoic acid and their influence on lipogenic enzyme activities in mouse liver

High carbohydrate (65% glucose) diets containing cis-12-octadecenoic acid (12c-18:1) or trans-9,trans-12-octadecadienoic acid (9t,12t-18:2) were fed to weanling mice to investigate the influence of fatty acid structure on six hepatic enzyme activities involved in lipid metabolism. Results with these diets were compared to those with diets containing no fatty acids, saturated fatty acids; cis-9-octadecenoic acid (9c-18:1) and cis-9,cis-12-octadecadienoic acid (9c,12c-18:2). These comparisons show saturated fatty acids, 9c-18:1, 12c-18:1, and 9t,12t-18:2, had little or no influence on the activity levels of fatty acid synthetase, malic enzyme (EC 1.1.1.40)citrate cleavage enzyme (EC 4.1.3.8), glucose-6-phosphate dehydrogenase (EC 1.1.1.49), 6-phosphogluconate dehydrogenase (EC 1.1.1.44) and acetyl-CoA carboxylase (EC 6.4.1.2). Neither 12c-18:1 nor 9t,12t-18:2 produced the dramatic enzyme-lowering effect exhibited by the diet containing 9c,12c-18:2 when compared to the diet devoid of fat. Thus, both the 9 and 12 bonds must be present in the same molecule. Also, at least one and probably both bonds must be in the cis configuration to depress liver enzyme activities. Capillary gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) were both used for analysis of the methyl esters derived from the hepatic lipids. The GC and GC-MS data provided (a) direct evidence for incorporation of both isomers into hepatic lipids and (b) indirect evidence that 9t,12t-18:2 lowered liver delta 9-desaturase activity. In addition, since these products were found in the complex liver lipids, there is no doubt that the various enzymes concerned with activation and acylation utilize both of these isomeric fatty acids as substrates.