Voluntary wheel running enhances neuronal BDNF in very old C57BL/6 mice

Abstract

Aging can lead to cognitive impairment in many individuals, with certain brain regions becoming less active and protein expression decreasing. However, it is possible to slow cognitive decline and preserve brain health with physical activity, which can increase levels of important brain proteins such as BDNF. To determine the impact of exercise on various brain proteins, voluntary wheel running (VWR) was observed in aged C57BL/6 mice for 3 days. VWR not only measures muscle performance but also serves as a non-stressful protocol that distinguishes it from forced activity, such as treadmill running or swimming, and more closely mimics natural animal behavior. Following VWR, immunohistochemistry was performed, and tissue scans were analyzed for BDNF, ATG5, and IL6. Expression of these proteins, linked to inflammation, aging, and cell damage, respectfully, was assessed in the hippocampus, neocortex, and the hypothalamus. Analysis revealed that VWR increased BDNF expression in the hippocampus and hypothalamus. The effects of VWR on BDNF, ATG5, and IL6 protein expression differed by brain region and varied between sexes. These results suggest that voluntary exercise may serve as a practical intervention to preserve cognitive function at very old ages.  

Keywords: BDNF, voluntary wheel running, aging intervention