Plasma lipid fatty acid composition and metabolism of 13C-labeled linoleic acid in preterm infants fed a formula containing medium-chain triacylglycerols

Maria Rodriguez, Simone Kiss, Maria Fink, Hans Demmelmair, Marco Turini, Gayle Crozier, and Berthold Koletzko

Div. Metabolic Disorders & Nutritional Medicine, Dr von Hauner Children's Hospital, Univ of Munich, Muenchen, Bavaria D-80337

Corresponding Author: bkoletz{at}kk-i.med.uni-muenchen.de

Most preterm infant formulas contain medium-chain triacylglycerols (MCT), but the effects of MCT on polyunsaturated fatty acid status and metabolism are still controversial.. Thus Using stable isotope methodology we studied the effects of MCT in infant formulas on the metabolism of linoleic acid metabolism in preterm infants using stable isotopes. Enterally fed preterm infants (n=19) were randomised ly assigned to receive for 7 days a preterm infant formula with 40% of fat as MCT (MCT group, n=10) or a formula without MCT (control group, n=9), with otherwise similar composition and similar linoleic and a-linolenic acid content. At study day 5, infants received orally 2 mg/kg body weight of uniformly 13C labeledlabelled linoleic acid. Fatty acids in plasma lipid classes and 13C enrichment of phospholipid fatty acids were measured 24h and 48h thereafter, and tracer oxidation was monitored by breath gas analysis. In comparison Compared to the control group, the MCT group showed lower recovery of 13C in breath 13CO2 (3.0% vsvs. 5.6% of the applied dose, p<0.01) and higher plasma triacylglycerol contents of octanoic acid, of decanoic acid and of total long-chain polyunsaturated fatty acids (57.1±4.4 µmol/L vs. 37.9±4.8 µmol/L, p<0.01, p < 0.05). Furthermore,Concentrations of several polyunsaturated fatty acids concentrations in plasma phospholipids and free non esterified fatty acids were higher in the MCT group. 13C concentrations in phospholipid n-6 fatty acids indicated no difference in the relative conversion of linoleic to arachidonic acid. We conclude that oral MCT effectively reduce linoleic acid oxidation and enhance total polyunsaturated fatty acid and n-6 long chain polyunsaturated fatty acid tissue availabilityoxidation in preterm infants, without compromising endogenous n-6 long chain polyunsaturated fatty acid synthesis, because the relative conversion of linoleic acid into its longer chain metabolites is not altered.

Add to CiteULike CiteULike Add to Complore Complore Add to Connotea Connotea Add to Del.icio.us Del.icio.us Add to Digg Digg Add to Reddit Reddit Add to Technorati Technorati What's this?

This article has been cited by other articles:

H.-W. Hsu, T. H. Zytkovicz, A. M. Comeau, A. W. Strauss, D. Marsden, V. E. Shih, G. F. Grady, and R. B. Eaton
Spectrum of Medium-Chain Acyl-CoA Dehydrogenase Deficiency Detected by Newborn Screening
Pediatrics, May 1, 2008; 121(5): e1108 - e1114.
[Abstract] [Full Text] [PDF]

F. Lehner, H. Demmelmair, W. Roschinger, T. Decsi, M. Szasz, K. Adamovich, R. Arnecke, and B. Koletzko
Metabolic effects of intravenous LCT or MCT/LCT lipid emulsions in preterm infants
J. Lipid Res., February 1, 2006; 47(2): 404 - 411.
[Abstract] [Full Text] [PDF]

All ASBMB Journals	Journal of Biological Chemistry
Molecular and Cellular Proteomics	ASBMB Today

				F. Lehner, H. Demmelmair, W. Roschinger, T. Decsi, M. Szasz, K. Adamovich, R. Arnecke, and B. Koletzko Metabolic effects of intravenous LCT or MCT/LCT lipid emulsions in preterm infants J. Lipid Res., February 1, 2006; 47(2): 404 - 411. [Abstract] [Full Text] [PDF]