Increased uptake of dietary retinoids at the maternal-fetal barrier in the nitrofen model of congenital diaphragmatic hernia.

[congenital diaphragmatic hernia]

The retinol signaling pathway is disrupted in congenital diaphragmatic hernia (CDH ). Since there is no fetal retinol synthesis , maternal retinol has to cross the placenta . Nitrofen interferes with the retinol-binding protein (RBP ) transfer pathway in CDH . However , in RBP knockout mice , retinol has been shown to be present . In this model , increased uptake of maternal dietary retinyl ester (RE ) bounded in low -dense -lipoprotein (LDL ) through low -density-lipoprotein-receptor 1 (LRP 1 ) and increased activity of RE hydrolysis by lipoprotein-lipase (LPL ) have been found . The aim of this study was to investigate the RE transfer pathway in the nitrofen CDH model .Pregnant rats were treated with nitrofen or vehicle on gestational day (D 9 ) and sacrificed on D 21 . Immunohistochemistry was performed to evaluate LRP 1 and LPL protein expression . Serum LDL levels were measured by ELISA . Pulmonary and serum retinoid levels were measured using HPLC .Markedly increased trophoblastic and pulmonary LRP 1 and LPL immunoreactivity were observed in CDH compared to controls . Significantly increased serum LDL and RE levels were observed in CDH compared to controls .The increased uptake of dietary retinoids at the maternal -fetal barrier in the nitrofen CDH model suggests that the RE transfer pathway may be the main source of retinol in this model .