Maternal Plasma Glycerophospholipids LC-PUFA Levels Have a Sex-Specific Association with the Offspring’s Cord Plasma Glycerophospholipids-Fatty Acid Desaturation Indices at Birth

Fatty acid desaturases, the enzymes responsible for the production of unsaturated fatty
acids (FA) in fetal tissues, are known to be influenced by maternal-placental supply of nutrients
and hormones for their function. We hypothesize that there could be a gender-specific regulation
of unsaturated FA metabolism at birth, dependent on the maternal fatty acid levels. In this study,
153 mother-newborn pairs of uncomplicated and ‘full-term’ pregnancies were selected and the FA
composition of plasma glycerophospholipids (GP) was quantified by gas chromatography. The FA
composition of mother blood plasma (MB) was compared with the respective cord blood plasma (CB)
of male newborns or female newborns. Product to substrate ratios were estimated to calculate delta 5
desaturase (D5D), delta 6 desaturase (D6D) and delta 9 stearoyl-CoA-desaturase (D9D/SCD) indices.
Pearson correlations and linear regression analyses were employed to determine the associations between
MB and CB pairs. In the results, the male infant’s MB-CB association was positively correlated
with the SCD index of carbon-16 FA, while no correlation was seen for the SCD index of carbon-18
FA. Unlike for males, the CB-D5D index of female neonates presented a strong positive association
with the maternal n-6 long chain-polyunsaturated FA (LC-PUFA), arachidonic acid. In addition, the
lipogenic desaturation index of SCD18 in the CB of female new-borns was negatively correlated with
their MB n-3 DHA. In conclusion, sex-related differences in new-borns’ CB desaturation indices are
associated with maternal LC-PUFA status at the time of the birth. This examined relationship appears
to predict the origin of sex-specific unsaturated FA metabolism seen in later life