Dietary supplementation in animal models of neurodevelopmental disorders

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The behavioural problems associated with Fetal Alcohol Syndrome (FAS) and Attention Deficit Hyperactivity disorder (ADHD) in humans include difficulties with learning and memory. We use animal models to understand the biological mechanisms underlying these conditions, addressing whether specific dietary supplements may prove useful as preventive and/or rehabilitative interventions.We have shown that if young rats are exposed to ethanol during the time when their brain is growing most rapidly, they will show impairments in short-term memory that are related to changes in gene-expression in the hippocampus, a brain region associated with memory storage. An increase in the amount of choline in the diet of young rats has been shown to result in memory enhancement and an increase in growth factors in the hippocampus. Thus we propose to examine whether such dietary treatment will have beneficial effects on memory proceses in ethanol-exposed rats. To this end we will feed young rats amounts of ethanol equivalent to those consumed by heavy "binge-drinking" pregnant women and at the same time supplement their diets with choline. We expect that these rats will show better short-term memory for the location of a hidden escape platform in a water-maze than rats fed ethanol, but not choline; we also expect that the dietary treatment will  reverse the changes seen in their brains.We are also in the process of completing a series of studies on learning and memory in spontaneously hypertensive rats (SHR, a recognised animal model of ADHD). Our preliminary findings indicate that, in comparison to normal rats, SHR make more mistakes on learning tasks, not because they are unable to remember, but because they cannot inhibit the wrong response. These rats also show abnormalities in the fatty acid composition of their brain, which may in turn be related to their behavioural problems through effects on specific chemical messengers. Thus we propose to supplement the diet of these rats with docosahexaenoic acid (DHA, an omega-3 fatty acid) to see whether we can improve their behavioural capabilities. The findings from these studies may have useful implications for the human conditions that they model.