title: Effect of three intravenously administered fat emulsions containing different concentrations of fatty acids on the plasma fatty acid composition of premature infants.
abstract: The effects of an intravenously administered lipid emulsion supplemented with gamma-linolenic acid on the fatty acid profile of premature infants were compared with those of two conventional lipid emulsions. Fifty-nine premature neonates receiving total parenteral nutrition were randomly assigned to receive either fat emulsion containing gamma-linolenic acid and long-chain triglycerides (LCT), an LCT emulsion, or a 50% (wt/wt) mixture of medium-chain triglycerides and LCT emulsion. Forty-nine infants completed the study. During the 6-day study there was a significant tenfold increase in the plasma levels of gamma-linoleic acid in the supplemented group versus the other two groups. A significant threefold to fivefold increase in the omega 6 long-chain polyunsaturated fatty acids was observed in all groups. These changes seemed to be attributable mostly to linoleic acid from the lipid emulsion, despite the 50% lower dose in the medium- and long-chain triglycerides group. The increase in the omega 3 long-chain polyunsaturated fatty acids also was mainly caused by a similar increase in the level of alpha-linolenic acid. No differences were recorded in the linoleic/alpha-linolenic acid ratio among the groups. Plasma levels of some of the semiessential fatty acids were significantly higher in the medium- and long-chain triglycerides group than in the LCT group. This may be related to slower elimination of LCT, to the difference between emulsions, or to less substrate inhibition on delta-6-desaturase, which seems to be less of a rate-limiting enzyme than previously considered. Further intravenous feeding trials are needed to identify the optimal balance of fatty acids for nutrition of these premature infants.
authors.affiliation: Department of Surgery A, Beilinson and Hasharon Medical Center, Sackler School of Medicine, Tel-Aviv University, Israel.
authors.forename: M
authors.initials: M
authors.lastname: Rubin
authors.forename: A
authors.initials: A
authors.lastname: Moser
authors.forename: N
authors.initials: N
authors.lastname: Naor
authors.forename: P
authors.initials: P
authors.lastname: Merlob
authors.forename: R
authors.initials: R
authors.lastname: Pakula
authors.forename: L
authors.initials: L
authors.lastname: Sirota
mesh_terms: D004311:Double-Blind Method; D005217:Fat Emulsions, Intravenous / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D005228:Fatty Acids, Essential / Q000008:administration & dosage / Q000097:blood; D015525:Fatty Acids, Omega-3 / Q000097:blood; D005231:Fatty Acids, Unsaturated / Q000097:blood*; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D010289:Parenteral Nutrition, Total; D014280:Triglycerides / Q000008:administration & dosage; D017965:gamma-Linolenic Acid / Q000008:administration & dosage / Q000097:blood
chemical_list: D005217:Fat Emulsions, Intravenous; D005228:Fatty Acids, Essential; D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated; D014280:Triglycerides; D017965:gamma-Linolenic Acid