Prenatal choline supplementation mitigates the adverse effects of prenatal alcohol exposure on development in rats

Abstract

Prenatal alcohol exposure can lead to a range of physical, neurological, and behavioral alterations referred to as fetal alcohol spectrum disorders (FASD). Variability in outcome observed among children with FASD is likely related to various pre- and postnatal factors, including nutritional variables. Choline is an essential nutrient that influences brain and behavioral development. Recent animal research indicates that prenatal choline supplementation leads to long-lasting cognitive enhancement, as well as changes in brain morphology, electrophysiology and neurochemistry. The present study examined whether choline supplementation during ethanol exposure effectively reduces fetal alcohol effects. Pregnant dams were exposed to 6.0g/kg/day ethanol via intubation from gestational days (GD) 5-20; pair-fed and lab chow controls were included. During treatment, subjects from each group received choline chloride (250mg/kg/day) or vehicle. Physical development and behavioral development (righting reflex, geotactic reflex, cliff avoidance, reflex suspension and hindlimb coordination) were examined. Subjects prenatally exposed to alcohol exhibited reduced birth weight and brain weight, delays in eye opening and incisor emergence, and alterations in the development of all behaviors. Choline supplementation significantly attenuated ethanol's effects on birth and brain weight, incisor emergence, and most behavioral measures. In fact, behavioral performance of ethanol-exposed subjects treated with choline did not differ from that of controls. Importantly, choline supplementation did not influence peak blood alcohol level or metabolism, indicating that choline's effects were not due to differential alcohol exposure. These data indicate early dietary supplements may reduce the severity of some fetal alcohol effects, findings with important implications for children of women who drink alcohol during pregnancy.

Figure 1

Mean (+ SEM) brain weight on PD 1. Brains of ethanol-exposed weighed significantly less than both control groups and choline significantly increased brain weight in all groups. There was no significant interaction between ethanol and choline treatment. * = vehicle treated groups significantly different from choline treated groups, ** = EtOH significantly different from both control groups

Figure 2

Percent of subjects who exhibited a mature surface righting reflex across PD 2-7. Fewer EtOH + Vehicle subjects showed a mature response compared to the LC + Choline subjects on PD 4 and compared to all other groups except the LC + Vehicle group on PD 5. * = significantly different from LC + Choline; ** = significantly different from all other groups except LC + Vehicle group

Figure 3

Percent of subjects successful on PD 6 (A) and mean (+/− SEM) latency to retract from the cliff over testing days (B). On PD 6, subjects exposed to prenatal alcohol and treated with vehicle were more successful and had significantly shorter latencies compared to all other groups. On subsequent days (PD 7-9), ethanol-exposed subjects were faster than LC controls and on PD 9, choline-treated subjects were faster than vehicle-treated subjects (Panel B). *** = EtOH + Vehicle significantly different from all other groups, * = EtOH significantly different from LC, ** = choline significantly different from vehicle

Figure 4

Percentage of successful responses on the geotaxic reflex task over testing days. On PD 7, ethanol-exposed subjects treated with vehicle were less successful compared to all groups except the LC + vehicle group. ** = significantly different from all groups except LC + vehicle

Figure 5

Age of first successful grip (A) and percent of subjects successful for 2 trials/day over the course of training (B). Ethanol delayed the ability to grip the bar for 30 seconds. Although ethanol-exposed subjects treated with choline exhibited this behavior earlier, there was no significant interaction of alcohol and choline. In contrast, fewer subjects exposed to ethanol and treated with vehicle were successful for 2 trials/day compared to all other groups, including the ethanol-exposed subjects treated with choline. *** = significantly different from all other groups, ** = significantly different from both control groups

Figure 6

Ethanol exposure significantly delayed hindlimb coordination and choline did not significantly mitigate this effect. ** = EtOH significantly different from both control groups