The Fatty Acid Composition of Human Thoracic Duct Lymph Lipids *

Abstract

Fernandes, Van de Kamer and Weijers (1) in studying a child with chylothorax found that the pattern of the fatty acids in the chyle was influenced by the kind of fat fed, but significant differences between chyle and dietary fat always remained. Recent experiments with carboxyl-labeled fatty acids by Blomstrand and co-workers (2-4) indicate that the chyle triglycerides constitute the main transport form of ingested fatty acids in man. Detailed information about the influence of dietary fatty acids on the fatty acid composition of the different lipid classes of human chyle is, however, still lacking. Furthermore, in order to effectively evaluate studies on the postabsorptive metabolism of chylomicron fatty acids, it is necessary to ascertain the nature of the fatty acid components of the various chyle lipids of thoracic duct lymph.Development of methods for obtaining thoracic duct lymph from human beings (5) and the analysis by gas-liquid chromatography (GLC) of the different lipids of human chyle after feeding a well defined triglyceride has made it possible to study the relationship between the fatty acid patterns of the different lymph lipid classes and the dietary fat. EXPERIMENTALExperimental design. Patient A of this study was a 56 year old man with inoperable adenocarcinoma of the left lung. He was in good condition during the whole investigation. He was nourished for 6 days solely by an orally administered liquid formula (Table I) supplemented with vitamins and minerals (6). The daily intake of formula was divided into 5 equal portions fed at 7 and 10 a.m. and at 1, 4 and 7 p.m. Tea or coffee was offered ad libitum. The fat in the formula diet con-

The intestinal absorption and metabolism of vitamin A and beta-carotene in man.

“…The ratio of palmitate to stearate, at the a' position, was 1.31 and 1.37 in the two samples. These results are in accord with previously reported observations on the fatty acid distribution in human lymph lecithin (13).…”

“…Analyses were also carried out to determine the fatty acid composition of the lecithin present in the chylomicron samples of studies I and III. It is known that lecithin comprises the major phospholipid in rat (12) and human (13) lymph and that the composition of lymph lecithin is relatively fixed, regardless of the composition of the diet (11)(12)(13). Furthermore, it has been pointed out (7) that, in the rat, the composition of the fatty acids attached to the a' position of lymph lecithin strongly resembles the fatty acid composition of newly absorbed lymph retinyl esters.…”

Heterogeneity of Fat Particles in Plasma During Alimentary Lipemia*

“…Primary particles in plasma showed a similar mobility. During maximal influx of dietary fat, the fatty acid composition of the primary particles resembled that of the fed fat, as in observations made on lymph (25)(26)(27) and on large particles isolated from lipemic plasma by centrifugation (6, …”

Effects of dietary fats on plasma lipids and lipoproteins: an hypothesis for the lipid-lowering effect of unsaturated fatty acids

“…It is well documented (29,30) that a single fat meal alters the fatty acid composition of chylomicron triglyceride, such that they become more like that of the dietary fat. On the other hand, the lipids of the lipoproteins in normal fasting plasma remain unaltered after a single meal, and approach the fatty acid composition of the dietary fat only after continuous feeding for several weeks or longer (31,32).…”