26856
The Effects of Maternal High Fat Diet on BTBR and B6 Offspring on Reversal Learning in the Water T-Maze.
The etiology for most cases of autism spectrum disorder (ASD) is unknown at this time. There is strong evidence for the genetic role in ASD but environmental factors also have a modifying role. One potential environmental factor is the maternal diet during fetal development. Obesity before and during prenatal development increases the vulnerability of affective disorders including schizophrenia and ASD. Prenatal maternal obesity has been shown to be a risk factor for ASD and other developmental disabilities (Krakowiak et al. Pediatrics 2012;129;e1121).
Objectives:
The objective of these experiments was to determine if a maternal high fat diet affected reversal learning in C57BL/6J and BTBR T+ tf Itpr/J (BTBR) offspring.
Methods:
Female C57BL/6J and BTBR mice were placed on either a high fat diet (60 kcal% fat D12492, Research Diets Inc, NJ) or a control diet (45 kcal% fat D12451, Research Diets Inc, NJ) for 2 weeks and then mated. The dams and pups remained on the diet through weaning and then were placed on regular mouse chow. One male and female pup per litter were tested as adults in the water T-maze and reversal test. Training trials for acquisition began with 10 trials per day for 3-days and were followed by reversal training (where the escape platform was moved to the opposite arm) for 2 days of 10 trials. The first arm entered was noted for each trial.
Results: All of the mice learned at the same rate suggesting that acquisition learning was not affected by the high fat diet or mouse strain. However, there were differences among the groups of mice during reversal learning. The BTBR mice prenatally exposed to the high fat diet learned the reversed arm more slowly compared to the BTBR pups from the dams on the control diet, as shown by the increased number of errors during reversal training. The C57BL/6J offspring were not affected by the maternal diet during reversal training as there were no differences in the number of errors between the high fat diet offspring and the control diet offspring.
Conclusions:
The results from the water T-maze reversal trials indicate that the C57BL/6J offspring demonstrated no changes in learning when exposed to the high fat diet during gestation. The offspring from the mouse model of ASD exposed to the maternal high fat diet showed no impairments in acquiring the water T-maze task, but were impaired in reversal learning. This suggests that the mouse model of ASD is more susceptible to environmental stressors affecting reversal learning, one of the core symptoms of ASD.