The effects of choline availability from gestation to early development on brain and retina function and phospholipid in a mice model
Choline is known to be essential for brain development and neural function, but its impact on the retina, as a type of neural tissue, is unknown. This study examined the effects of choline during fetal development on membrane phospholipid (PL) compositions and functions in neural tissues, brain and retina. Pregnant C57 BL/6 mice were fed one of the 4 choline modified diets from gestation to early development: i) deficient (Def, 0g/kg), ii) control (Cont, 2.5g/kg), iii) supplemented with choline chloride (Cho, 10g/kg), iv) supplemented with egg phosphatidylcholine (PC) (PC, 10g/kg). On postnatal day (PD) 7, pups were culled to 4 from each dam, and kept on the same respective diets until 45 PD. On PD 35, memory function was measured by Morris water maze and on PD 45, retina function by an electroretinogram. Brain and retina were obtained for PL analysis by 31P NMR. Animals on the Def and PC diets were lower in body weights on PD 7, in comparison to the other two groups. While the Def group caught up in weights to its Cont counterparts, the PC group’s weight stayed consistently low until PD 45 (P<0.03). As for brain function, Cho and PC supplemented groups showed enhanced cued learning task, and spatial memory abilities, respectively, whereas the Def group showed the poorest memory recollection (P<0.05). The ERG amplitudes of rod driven photoreceptors and inner neural cell functions were significant (P<0.05) in the following order: Cont > Def > PC > Cho, at all light intensities, without reaching statistical significances in cone-driven responses. There were no differences in major PL compositions in the brain and retina. PC enriched group had increased subclasses of ether PL, PEaa and PCaa in the brain. These results indicate that while the addition of choline supplementation is beneficial for fetal brain development and function during early developmental stages, its contributions in the retina were minor. The effect of choline to the membrane PL structure was negligible for the stage of development in the given experimental design.
choline, development stage