Effects of Six Months of Treadmill Running on Amyloid Beta, Plaque Load, and Behavior in TG2576 Mice

Studies indicate that environmental enrichment and physical activity have a positive effect on the pathology in transgenic AD mice. However, they have failed to examine the positive effects of exercise independent from environmental enrichment. The dose response of exercise has yet to be studied in transgenic mouse models of AD. This study attempted to answer these questions by examining the individual effects of a 6-month exercise regimen on plaque load, Aβ levels, and behavior in the 9 months of age Tg2576 mouse model of Alzheimer\u27s disease. Mice were socially housed in an enriched environment and divided into two groups. The run group consisted of mice running daily on a motorized treadmill with a shock grid for motivation at 10m/min (n=8) and 15m/min (n=7). The sedentary control group (n=15) consisted of mice that were placed on the treadmill with only the shock grid turned on. All mice were sacrificed at 9 months of age after the 6 month exercise regimen. Behavioral analysis (conducted prior sacrifice), histology, and soluble Aβ analysis were conducted. I found an improvement in recognition memory in the run group compared to the sedentary control group, but no improvement in spatial memory was noted for either group. There was a difference in plaque accumulation between the two groups and a decrease in soluble Aβ levels in the run group compared to the sedentary control group