Authors: Meagan Hoppe, Abbi Hernandez, Caesar Hernandez, Keila Campos, Joe McQuail, Sara Burke
Faculty Mentor: Sara Burke
College: College of Medicine
With advancing age comes declining cognitive function. The potential to reverse these changes with dietary intervention holds promise for improving the quality of life of millions facing age-related cognitive decline. The prefrontal cortex (PFC) and hippocampus (HPC) are critical for supporting higher cognitive function, and both experience age-related decline in distinct ways. Previously, we investigated the ketogenic diet (KD) as a means for ameliorating declining cognitive function. However, the mechanism(s) of efficacy remain largely unknown. Therefore, this study investigated whether a KD alters synapse-related protein composition within the HPC of young and aged rats. Western blotting was used to quantify 10 synaptic proteins in the HPC synaptosome. Although this dietary regimen results improved cognitive outcomes, no protein levels were significantly altered by the KD. Additionally, Western blotting was used to compare membrane and cytosolic levels of the glucose transporter GLUT4, which is mobilized in response to insulin. Interestingly, young rats had differential expression of GLUT4 across brain regions. Furthermore, while aged rats had significantly altered GLUT4 mobilization relative to young in the PFC, this was ameliorated in aged KD-fed rats. Together, these data suggest KDs work through restoration of metabolism-related impairments rather than through synapse-related protein expression within the HPC.