Environmental Enrichment Mitigates Detrimental Cognitive Effects of Ketogenic Diet in Weanling Rats.

For decades, the ketogenic diet has been an effective treatment of intractable epilepsy in children. Childhood epilepsy is pharmacoresistant in 25-40 % of patients taking the current prescribed medications. Chronic seizure activity has been linked to deficits in cognitive function and behavioral problems which negatively affect the learning abilities of the child. Recent studies suggest the ketogenic diet (KD), a high fat with low carbohydrate and protein diet, has adverse effects on cognition in weanling rats. The diet reduces circulating glucose levels to where energy metabolism is converted from glycolysis to burning fat and generating ketone bodies which has been suggested as a highly efficient source of energy for the brain. In contrast, when weanling rats are placed in an enriched environment, they exhibit increased spatial learning, memory, and neurogenesis. Thus, this study was done to determine if weanling rats being administered a KD in an environmental enrichment (EE) would still exhibit the negative cognitive effects of the diet previously observed. The present study suggests that an altered environment is capable of reducing the cognitive deficits in weanling rats administered a KD. Learning was improved with an EE. The effect of diet and environment on anxiety and depression suggests a significant reduction in anxiety with enrichment rearing. Interestingly, circulating energy substrate levels were increased in the EE groups along with brain-derived neurotrophic factor despite the least changes in weight gain. In light of numerous studies using KDs that seemingly have adverse effects on cognition, KD-induced reductions in excitotoxic events would not necessarily eliminate that negative aspect of seizures.