The effects of dietary trans, trans methyl octadecadienoate acid on composition and fatty acids of rat heart

Abstract

Traits, trans linoleate (18:2) as the sole source of dietary fat (10% of calories) for 12 weeks induced the typical symptoms of essential fatty acid deficiency in rats and markedly altered the gross and lipid composition of hearts. The cardiac protein and phospholipids were decreased compared to rats receiving adequate cis, cis linoleate, i.e., 180.0 and 18.5 versus 214.4 and 23.8 mg/g heart, respectively, while DNA levels were 1.4 and 1.2 mg/g heart tissue, respectively. The hearts from rats on trans. trans 18:2 contained less phosphatidylcholine than hearts from rats on an essential fatty acid deficient diet of hydrogenated coconut fat or rats fed an essential fatty acid sufficient diet. The fatty acid composition of the various cardiac lipid classes were markedly affected by dietary fatty acids. The levels of cis, cis 18:2n6 and 20:4n6 were depressed in lipids from hearts of rats on traits, trans 18:2 or hydrogenated coconut fat diets while 18: 1n9 and 20:3n9 were increased compared to rats receiving cis, cis 18:2. However, the amount of 20:3n9 was much lower in the trans, trans 18:2 group compared to the hydrogenated coconut fat group indicating that the dietary trans 18:2 depressed the elongation and further desaturation of 18:1n9 which, with 16:1 and trans, trans 18:2, accumulated in the cardiac lipids of the rats fed trans 18:2. There was a marked increase in 22:5n6 in phosphatidylcholine of rats receiving cis, cis C 18:2 as sole source of fat. Am. J. Clin. Nutr. 33: 598-605, 1980.