Dietary nucleotides enhance plasma lecithin cholesterol acyl transferase activity and apolipoprotein A-IV concentration in preterm newborn infants.
The activity of lecithin cholesterol acyl transferase (LCAT), a key enzyme in lipoprotein metabolism, is low in newborn preterm infants. It has been suggested that a normal gastrointestinal function might be necessary to induce a postnatal increase of LCAT activity because apoproteins A-I and A-IV (apoA-I and apoA-IV) synthesized in considerable amounts in the intestine are known activators of LCAT. Dietary nucleotides have been reported to enhance intestinal growth and maturation; therefore, we hypothesized that nucleotide supplementation to formulas for preterm infants may influence LCAT activity. To investigate this hypothesis, two groups of preterm infants were fed either a nucleotide-free formula or a nucleotide-supplemented formula during the first month of life. The plasma LCAT activity, plasma levels of apoA-I and apoA-IV, plasma cholesteryl esters, and plasma fatty acid composition of cholesteryl esters and phospholipids were then determined. Infants receiving nucleotides had higher LCAT activities and apoA-IV levels than those receiving the nucleotide-free formula for a few weeks. The changes in apoA-IV levels were highly correlated with those of the LCAT activities. However, there were no significant correlations between changes in LCAT activity and plasma cholesteryl esters or phospholipids. These findings indicate that nucleotide supplementation to formulas for preterm infants may improve dietary lipid tolerance by enhancing plasma LCAT activity, probably as a result of an increase in apoA-IV plasma concentrations; they also suggest that nucleotides may enhance apoA-IV synthesis in the intestine during the neonatal period.
Sánchez-Pozo
A
A
Department of Biochemistry and Molecular Biology, University of Granada, Spain.
Ramírez
M
M
Gil
A
A
Maldonado
J
J
van Biervliet
J P
JP
Rosseneu
M
M
D016632:Apolipoprotein A-I / Q000097:blood*; D001054:Apolipoproteins A / Q000097:blood*; D002788:Cholesterol Esters / Q000097:blood / Q000737:chemistry; D005227:Fatty Acids / Q000032:analysis; D006801:Humans; D007225:Infant Food; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D009711:Nucleotides / Q000494:pharmacology*; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000097:blood*; D010743:Phospholipids / Q000097:blood / Q000737:chemistry
D016632:Apolipoprotein A-I; D001054:Apolipoproteins A; D002788:Cholesterol Esters; D005227:Fatty Acids; D009711:Nucleotides; D010743:Phospholipids; C022205:apolipoprotein A-IV; D007862:Phosphatidylcholine-Sterol O-Acyltransferase