Plasma phospholipids indicate impaired fatty acid homeostasis in preterm infants.
BACKGROUND
During fetal development, docosahexaenoic (DHA) and arachidonic acid (ARA) are particularly enriched in brain phospholipids. After preterm delivery, fetal enrichment of DHA and ARA via placental transfer is replaced by enteral and parenteral nutrition, which is rich in linoleic acid (LA) instead. Specific DHA and ARA enrichment of lipoproteins is reflected by plasma phosphatidylcholine (PC) species, whereas plasma phosphatidylethanolamine (PE) composition reflects hepatic stores.


OBJECTIVE
We profiled PC and PE species in preterm infant plasma, compared with cord and maternal blood, to assess whether current feeding practice meets fetal conditions in these patients.


METHODS
Preterm infant plasma (N = 171, 23-35 w postmenstrual age (PMA), postnatal day 1-103), cord plasma (N = 194) and maternal serum (N = 121) (both 24-41 w PMA) were collected. After lipid extraction, PC and PE molecular species were analyzed using tandem mass spectrometry.


RESULTS
Phospholipid concentrations were higher in preterm infant than in cord plasma after correction for PMA. This was mainly due to postnatal increases in LA-containing PC and PE, resulting in decreased fractions of their DHA- and ARA-containing counterparts. These changes in preterm infant plasma phospholipids occurred during the time of transition to full enteral feeds (day 0-10 after delivery). Thereafter, the fraction of ARA-containing phospholipids further decreased, whereas that of DHA slowly reincreased but remained at a level 50% of that of PMA-matched cord blood.


CONCLUSIONS
The postnatal increase in LA-PC in preterm infant plasma results in decreased fractions of DHA-PC and ARA-PC. These changes are also reflected by PE molecular composition as an indicator of altered hepatic fatty acid homeostasis. They are presumably caused by inadequately high LA, and low ARA and DHA supply, at a stage of development when ARA-PC and DHA-PC should be high, probably reducing the availability of DHA and ARA to the developing brain and contributing to impaired neurodevelopment of preterm infants.
Department of Neonatology, Faculty of Medicine, Eberhard-Karls-University, Calwer Straße 7, 72076, Tübingen, Germany, wolfgang.bernhard@med.uni-tuebingen.de.
Wolfgang
W
Bernhard
Marco
M
Raith
Vera
V
Koch
Rebecca
R
Kunze
Christoph
C
Maas
Harald
H
Abele
Christian F
CF
Poets
Axel R
AR
Franz
D016718:Arachidonic Acid / Q000097:blood*; D004281:Docosahexaenoic Acids / Q000097:blood*; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D006706:Homeostasis; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D019787:Linoleic Acid / Q000097:blood; D008297:Male; D010713:Phosphatidylcholines / Q000097:blood; D010714:Phosphatidylethanolamines / Q000097:blood; D010743:Phospholipids / Q000097:blood*; D011446:Prospective Studies
D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010743:Phospholipids; D004281:Docosahexaenoic Acids; D016718:Arachidonic Acid; C483858:phosphatidylethanolamine; D019787:Linoleic Acid