Absorption and distribution of deuterium-labeled trans- and cis-11-octadecenoic acid in human plasma and lipoprotein lipids.
Triglycerides of deuterium-labeled trans-11-, trans-11-cis-11- and cis-9-octadecenoic acid (11t-18:1-2H, 11c-18:1-2H) were simultaneously fed to two young adult male subjects. Plasma lipids from blood samples collected periodically for 48 hr were analyzed by gas chromatography-mass spectroscopy. The results indicate the delta 11-18:1-2H acids and 9c-18:1-2H were equally well absorbed; relative turnover rates were higher for the delta 11-18-1-2H acids in plasma triglycerides; incorporation of the delta 11-18:1-2H acids into plasma phosphatidylcholine was similar to 9c-18:1-2H, but distribution at the 1- and 2-acyl positions was substantially different; esterification of cholesterol with 11t-18:1 was extremely low; chain shortening of the delta 11-18:1-2H acids was 2-3 times greater than for 9c-18:1-2H; no evidence for desaturation or elongation of the 18:1-2H acids was detected; and a 40% isotopic dilution of the 18:1-2H acids in the chylomicron triglyceride fraction indicated the presence of a substantial intestinal triglyceride pool. Based on our present knowledge, these metabolic results for delta 11-18:1 acids present in hydrogenated oils and animal fats indicate that the delta 11 isomers are no more likely than 9c-18:1 to contribute to dietary fat-related health problems.
D002788:Cholesterol Esters / Q000097:blood; D003903:Deuterium; D004041:Dietary Fats / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007700:Kinetics; D008074:Lipoproteins / Q000097:blood*; D009829:Oleic Acids / Q000097:blood*; D010743:Phospholipids / Q000097:blood; D013237:Stereoisomerism; D014280:Triglycerides / Q000097:blood / Q000378:metabolism*
D002788:Cholesterol Esters; D004041:Dietary Fats; D008074:Lipoproteins; D009829:Oleic Acids; D010743:Phospholipids; D014280:Triglycerides; D003903:Deuterium; C050413:11-octadecenoic acid