linoleic-acid and Fetal-Growth-Retardation

This study evaluated the arachidonic acid (AA) and docosahexaenoic acid (DHA) formation from d5-labeled linoleic acid (d5-LA) and alpha-linolenic acid (d5-LNA) precursors in infants with intrauterine growth restriction (IUGR) compared with control groups matched by gestational age (GA) or birth weight. We compared DHA and AA formation from deuterated precursors d5-LA and d5-LNA in 11 infants with IUGR with 13 and 25 control subjects who were appropriate for GA and matched by GA and by birth weight, respectively. After an enteral administration of d5-LA and d5-LNA, we determined unlabeled and d5-labeled fatty acids at 24, 48, and 96 h in plasma. Absolute concentrations and area under the curve (AUC) over the 96-h study were used for analysis. Absolute concentration of d5-DHA and the product/precursor ratio of the d5-labeled AUCs indicated a less active DHA formation from LNA in infants with IUGR compared with their GA-matched (2-fold) and birth weight-matched (3-fold) control subjects. The ratios of eicosapentaenoic and n-3 docosapentaenoic acid to DHA were also affected. Similar evaluation for the n-6 series was not significant. DHA metabolism is affected in infants with IUGR; the restricted DPA to DHA conversion step seems to be principally responsible for this finding.

Topics: alpha-Linolenic Acid; Area Under Curve; Birth Weight; Deuterium; Docosahexaenoic Acids; Eicosapentaenoic Acid; Fatty Acids; Fatty Acids, Unsaturated; Fetal Growth Retardation; Humans; Infant, Newborn; Isotopes; Linoleic Acid; Time Factors

Fetuses with intrauterine growth restriction (IUGR) are at increased risk of death and disease during neonatal, pediatric, and adult life. Postnatal deficits in essential fatty acids have been associated with the neural and vascular complications of premature neonates. We studied whether fetal-maternal fatty acid relationships are already impaired in utero in IUGR fetuses. Fetal (F) and maternal (M) fatty acid profiles were determined in utero in 11 normal [appropriate for gestational age (AGA)] and in 10 IUGR fetuses by fetal blood sampling (FBS) between 19 and 39 wk. Total plasma fatty acid concentrations were significantly higher in M than in F of both AGA (M: 2.03 +/- 0.53 mg/mL; F: 0.64 +/- 0.29 mg/mL; p < 0.001) and IUGR (M: 2.16 +/- 0.59 mg/mL; F: 0.73 +/- 0.17 mg/mL; p < 0.001). The F/M ratio was significantly higher for linoleic acid (AGA: 0.36 +/- 0.09; IUGR: 0.52 +/- 0.12; p < 0.01) and significantly lower for the long-chain polyunsaturated fatty acid docosahexaenoic acid (AGA: 1.94 +/- 0.32; IUGR: 1.25 +/- 0.19; p < 0.05) and arachidonic acid (AGA: 2.35 +/- 0.35%; IUGR: 2.04 +/- 0.3%; p < 0.05) in IUGR compared with AGA pregnancies. The differences observed in the relative amounts but not in total plasma concentrations of fatty acid fetal-maternal relationships in pregnancies associated with IUGR could be related to inadequate transplacental supply as well as to a fetal lack of the enzymes necessary for elaboration of these metabolically relevant conditionally essential fatty acids. These differences might have a role in determining the biochemical environment leading to the neural and vascular complications associated with IUGR.

Topics: Arachidonic Acid; Docosahexaenoic Acids; Fatty Acids; Fatty Acids, Unsaturated; Female; Fetal Blood; Fetal Growth Retardation; Gestational Age; Humans; Linoleic Acid; Maternal-Fetal Exchange; Pregnancy