A comparison of the metabolism of eighteen-carbon 13C-unsaturated fatty acids in healthy women (original) (raw)

2003, The Journal of Lipid Research

Altered use of different dietary fatty acids may contribute to several chronic diseases, including obesity, noninsulin-dependent diabetes mellitus, and cardiovascular disease. However, few comparative data are available to support this link, so the goal of the present study was to compare the metabolism of [ 13 C]oleate, [ 13 C] ␣-linolenate, [ 13 C]elaidate, and [ 13 C]linoleate through oxidation and incorporation into plasma lipid fractions and adipose tissue. Each tracer was given as a single oral bolus to six healthy women. Samples were collected over 8 days, and 13 C was analyzed using isotope ratio mass spectrometry. At 9 h postdose, cumulative oxidation was similar for [ 13 C]elaidate, [ 13 C]oleate, and [ 13 C] ␣-linolenate (19 ؎ 1%, 20 ؎ 4%, and 19 ؎ 3% dose, respectively). Significantly lower oxidation of [ 13 C]linoleate (12 ؎ 4% dose; P Ͻ 0.05) was accompanied by its higher incorporation into plasma phospholipids and cholesteryl esters. Abdominal adipose tissue was enriched with [ 13 C] ␣-linolenate, [ 13 C]elaidate, or [ 13 C]linoleate within 6 h. The percentage linoleate in plasma phospholipids correlated positively with [ 13 C]linoleate and [ 13 C]elaidate oxidation, indicating a potential role of background diet. Conversion of [ 13 C]linoleate and [ 13 C] ␣-linolenate to longer chain polyunsaturates was a quantitatively minor route of utilization.-McCloy, U., M. A. Ryan, P. B. Pencharz, R. J. Ross, and S. C. Cunnane. A comparison of the metabolism of eighteen-carbon 13 C-unsaturated fatty acids in healthy women.