Vitamin A is vital during the initial stages of life. Important in embryonic development, tissue homeostasis, lipid metabolism and cellular differentiation and proliferation. Human placentae express factors for the nuclear transcription of retinoic acid receptors and retinoic X receptors. Modulation of these factors by retinoic acid modulates the expression of several genes such as: chorionic gonadotrophic bormone; placental lactogenic hormone; leptin; epidermal growth factor receptor; triiodothyronine; oestrogen; progesterone; cortisol; aldosterone; testosterone; vitamin D; cholesterol; and fatty acids.
This study examines the association between vitamin A deficiency measured by maternal serum retinol concentration, umbilical cord and placental concentration of retinol and carotenoids. This allows a defining of placental values representative of deficiency.
Two hundred and sixty-two mothers and their newborn babies were measured.
No difference between averages of placental retinol and carotenoids was observed in the puerperal women regardless of the cut-off point used to define vitamin A deficiency.
In the newborn babies there was a decrease in placental retinol values in individuals with vitamin A deficiency when a 1•05 umol/l cut-off point was adopted.
The placental carotenoid average concentration was reduced
This study shows an association between the placental concentration of retinol and carotenoids with clinical vitamin A deficiency.
Gomes et al 2010. Placenta: a possible predictor of vitamin A deficiency . British J Nutrition. vol 103 pp1340-1344
- Martin Eastwood