NERVONIC ACID IN RED-BLOOD-CELL SPHINGOMYELIN IN PREMATURE-INFANTS - AN INDEX OF MYELIN MATURATION

The present study addresses the question whether nervonic acid (24:1n- 9) accumulation in sphingomyelin (SM) of red blood cells (RBC) could y ield information on cerebrum maturation in premature infants. The stud y included 28 premature eutrophic infants of 31.5 wk gestational age. Eleven were fed with human milk, nine with a regular formula and eight with an alpha-linolenate-enriched formula. The fatty acid composition of the SM fraction was determined by gas-liquid chromatography on a 5 0-m fused silica capillary column. At 32 wk gestational age, the main fatty acids in SM were 16:0, 18:0, 20:0, 22:0, 24:0 and 24:1n-9. After five weeks of feeding, at week 37 of postconceptional age, the most s triking variation was a rise in 24:1n-9, from 9.9 +/- 0.7 to 12.8 +/- 0.9 (P < 0.02), regardless of regimen in all three feeding groups. The rise in 24:1n-9 after birth in premature eutrophic infants is the beg inning of a trend toward the higher levels in 24:1n-9 observed in matu re newborns and older infants. The 24:1n-9 level in SM of RBC from pre mature infants may reflect 24:1n-9 levels in SM of brain and could thu s reflect brain maturity.