Long-term aerobic exercise can prevent age-related brain changes, revealed a new study. Lead author Ileana Soto of The Jackson Laboratory said that their data suggested that normal aging causes significant dysfunction to the cortical neurovascular unit, including basement membrane reduction and pericyte loss.
In the study, the researchers provided mice with a running wheel from 12 months old (equivalent to middle aged in humans) and assessed their brains at 18 months (equivalent to 60 years old in humans, when the risk of Alzheimer's disease is greatly increased).
Young and old mice alike ran about two miles per night, and this physical activity improved the ability and motivation of the old mice to engage in the typical spontaneous behaviors that seem to be affected by aging.
The results showed that the exercise significantly reduced age-related pericyte loss in the brain cortex and improved other indicators of dysfunction of the vascular system and blood-brain barrier.
It also decreased the numbers of microglia or monocytes expressing a crucial initiating component of the complement pathway that others have shown previously to play are role in age-related cognitive decline.
Surprisingly, these beneficial effects of exercise were not seen in mice deficient in a gene called Apoe, variants of which are a major genetic risk factor for Alzheimer's disease. The study is published in the Journal PLOS