Endocrine Abstracts

Vitamin D binding protein (VDBP) has a critical role in orchestrating optimal vitamin D homeostasis and bioavailability. VDBP has been implicated in modulating the gene expression of amino-transporters within the placenta and might thus control the transfer of amino acids to neonates during in utero development. We hypothesize that dyshomeostasis of VDBP could lead to adverse metabolic profiles and low birth weight in neonates. VDBP genetic polymorphisms steer the unique interplay of VDBP biodynamics and pregnancy complications. The aim of this study was to investigate associations of maternal VDBP polymorphisms with neonatal anthropometric profiles at birth, according to different cut-offs of vitamin D status. We included 66 maternal-neonatal dyads recruited from Northern Greece. Serum 25(OH)D concentrations were determined using LC–MS/MS and VDBP was measured by ELISA. We classified maternal and neonatal vitamin D status at birth, according to 25-hydroxyvitamin D (25(OH)D) concentrations as follows: 25(OH)D ≤ 25 nmol/l (deficiency), 25–50 nmol/l (insufficiency) and 25(OH)D ≥ 50-75 nmol/l (sufficiency). Our results revealed that with maternal 25(OH)D <50 nmol/l neonatal anthropometry parameters including abdominal circumference, lower arm radial circumference and lower leg calf circumference were significantly higher in maternal VDBP genetic variants rs2298850 CG+GG and rs4588 CA+AA and rs7041 GT+TT. This relation between birth neonatal anthropometry and maternal VDBP polymorphism, was not significant for birth maternal 25(OH)D< 25 nmol/l. In conclusion, these findings, emphasize a potential role of functional polymorphisms, for maternal VDBP genotypes for rs2298850, rs7041 and rs4588, in conjunction with a maternal cut-off of maternal 25(OH)D in the range of sufficiency on neonatal growth and development. Further investigations are required to decipher the exact dynamic pathways of maternal VDBP and genetic variants on pregnancy complications and offspring body anthropometry.