From nutritional patterns to behavior: high-fat diet influences on inhibitory control, brain gene expression and metabolomics in rats

Impulsive and compulsive behaviors are associated with inhibitory control deficits. Diet plays a pivotal role in normal development, impacting both physiology and behavior. However, the specific effects of a high-fat diet (HFD) on inhibitory control have not received adequate attention. This study aimed to explore how exposure to a HFD from postnatal day (PND) 33 to PND77 affects impulsive and compulsive behaviors. The experiment involved 40 Wistar rats subjected to HFD or chow diets. Several tasks were employed to assess behavior, including variable delay to signal (VDS), five choice serial reaction time task (5-CSRTT), delay discounting task (DDT), and rodent gambling task (rGT). Genetic analyses were performed on the frontal cortex, and metabolomics and fatty acid profiles were examined by using stool samples collected on PND298. Our results showed that the HFD group exhibited increased motor impulsive behaviors while not affecting cognitive impulsivity. Surprisingly, reduced impulsive decision-making was shown in the HFD group. Furthermore, abnormal brain plasticity and dopamine gene regulation were shown in the frontal cortex, while metabolomics revealed abnormal fatty acid levels.