Effect of different levels of docosahexaenoic acid supply on fatty acid status and linoleic and α-linolenic acid conversion in preterm infants.
OBJECTIVE
Long-chain polyunsaturated fatty acid (LC-PUFA) enrichment of preterm infant formulas is recommended to meet high demands. Dietary LC-PUFA may inhibit endogenous LC-PUFA synthesis, thus limiting their benefit. We investigated effects of different docosahexaenoic acid (DHA) intakes on plasma and erythrocyte fatty acids and endogenous LC-PUFA synthesis in preterm infants.


METHODS
Forty-two preterm infants (birth weight 1000-2200 g) were randomized double-blind to preterm formulas with γ-linolenic acid (0.4%) and arachidonic acid (AA, 0.1%) but different DHA contents (A: 0.04%, B: 0.33%, C: 0.52%); 24 received human milk (HM: 0.51% AA, 0.38% DHA, nonrandomized). Blood was sampled on study days 0, 14, and 28. Uniformly C-labeled linoleic acid (2 mg/kg) and α-linolenic acid (1 mg/kg) were applied orally on day 26 and blood samples collected 48  hours later.


RESULTS
On day 28, group A had the lowest and group C the highest plasma phospholipid concentrations of eicosapentaenoic acid and DHA. Erythrocyte phospholipid DHA was lowest in group A, but comparable in groups B, C, and HM. Plasma and erythrocyte AA were lower in formula groups than in HM. DHA intake had no effect on DHA synthesis. LC-PUFA synthesis was lower in HM infants.


CONCLUSIONS
DHA supply dose dependently increased plasma DHA. Formula DHA levels of 0.33% matched plasma DHA status of infants fed HM. LC-PUFA synthesis was lower in infants fed HM than formulas with different DHA and low AA contents. With the LC-PUFA supplementation used, DHA in formulas did not inhibit AA or DHA synthesis.
University of Munich Medical Centre, Zentralklinikum Augsburg, Germany.
Ulrike C
UC
Sauerwald
Maria M
MM
Fink
Hans
H
Demmelmair
Patrick V
PV
Schoenaich
Astrid A M
AA
Rauh-Pfeiffer
Berthold
B
Koletzko
D016718:Arachidonic Acid / Q000097:blood*; D004041:Dietary Fats / Q000097:blood*; D004281:Docosahexaenoic Acids / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D015118:Eicosapentaenoic Acid / Q000097:blood*; D004912:Erythrocytes / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000096:biosynthesis; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D019787:Linoleic Acid / Q000097:blood*; D008297:Male; D008895:Milk, Human; D010743:Phospholipids / Q000097:blood*; D017962:alpha-Linolenic Acid / Q000097:blood*
D004041:Dietary Fats; D005231:Fatty Acids, Unsaturated; D010743:Phospholipids; D017962:alpha-Linolenic Acid; D004281:Docosahexaenoic Acids; D016718:Arachidonic Acid; D019787:Linoleic Acid; D015118:Eicosapentaenoic Acid