Investigation of Exercise Prescription on Diet-induced Changes in Memory, Cognition, and Hippocampal BDNF Levels

Exercise and diet influence cognitive health, but the role of exercise in mitigating long-term memory loss due to chronic consumption of a “Western Diet” remains unclear. Previous research in this area has yielded nonsignificant results. Thus, this study aims to investigate whether interval-running exercise can mitigate diet-induced cognitive decline, to pinpoint the neurological mechanism responsible for high-fat diet induced cognitive changes, and to fill a crucial gap in the literature. Male and female C57BL/6 mice were fed either a high-fat diet (HFD; 60% kcal from fat) or a control diet (CD; 14% kcal from fat) from postnatal day (PND) 21. At PND 56, groups from each diet remained sedentary or underwent an eight-week interval-running paradigm. Long-term memory was assessed at PND 84 using the radial arm maze (RAM) and object placement test (OPT). Brain samples were then collected to analyze brain-derived neurotrophic factor (BDNF) levels. In RAM, exercised HFD mice outperformed sedentary HFD counterparts, and no difference was found within exercised groups. In OPT, exercised HFD and CD mice showed greater novel object investigation, unlike sedentary groups. While BDNF data are incomplete, behavioral results indicate exercised subjects will have higher levels than sedentary counterparts. These findings highlight exercise as an effective intervention against diet-induced cognitive decline. The absence of differences among exercised groups suggests exercise can counteract memory impairment caused by chronic HFD consumption. This research supports the development of personalized exercise-based treatments for memory loss.