(711) Offspring neurobehavioral phenotype following maternal exercise versus sedentary behavior

Human epidemiological and animal studies show the maternal in utero environment significantly impacts offspring neurodevelopment and behavior. Neurobehavioral processes impacted by maternal programming include learning, memory, and anxiety. The aim of this study was to investigate neurobehavioral outcomes in offspring of sedentary mice versus mice that exercised in pregnancy.

Study Design:

C57BL/6J female mice were placed on control diet and allocated to sedentary (SED) versus voluntary running wheel exercise (EX) cages. Voluntary wheel running was allowed 2 weeks prior to breeding and throughout weaning. At 8 weeks of age, offspring neurobehavior was assessed via light/dark box to measure anxiety-type behavior and novel object testing to measure learning and memory behavior. Outcomes were analyzed by two-way ANOVA to assess main effects of exercise and sex, and their interaction. 

Results:

Neurobehavioral testing was completed in 11 male SED, 13 female SED, 14 male EX, and 13 female EX offspring. While there were no main effects of sex or exercise, there was a significant interaction effect for differences in exploration time (seconds: 7.636 male SED vs. 2.267 male EX vs. 0.385 female SED vs. 4.545 female EX; P<span class="s1">_Sex=0.272, P<span class="s1">_EX=0.788, P<span class="s1">_Int=0.038) during novel object testing, with learning and memory function appearing improved in female offspring but worsened in male offspring. There were no significant differences in anxiety-like behavior among groups. 

Conclusion:

These data suggest that while not impacting offspring anxiety-type behavior, maternal exercise appears to exert a differential effect on learning and memory function based on sex. More specifically, our data provide evidence that maternal exercise may have a detrimental effect on learning and memory in males while improving this functioning in female offspring. Future studies will examine differences in cytokine levels in the hippocampus, which could provide a biological explanation for these sex differences.