Effects of voluntary exercise on cerebral microvascular oxygenation in aged mice

Although the beneficial effects of regular physical exercise on brain aging and neurodegenerative diseases are well recognized, a clear understanding of how exercise leads to such benefits remains elusive. In this work, we investigated the effects of normal aging on cortical microvascular oxygenation, perfusion, and morphology and the impact of four months of voluntary wheel running on cortical microvascular oxygenation in 20 months old mice. We used two-photon microscopy to assess age-related and exercise-induced changes in the distributions of capillary oxygen partial pressure (PO2) and red-blood-cell flux across cortical depth in awake mice. Our finding suggests the mitigating effect of exercise on the progression of age-related changes in capillary oxygenation in deeper cortical layers which may be related to health-enhancing benefits of exercise in elderly individuals.