LACK of physical activity is known to increase a person’s risk of Alzheimer’s disease.
A new study in mice suggests that exercise may protect against Alzheimer’s by improving the regulation of iron metabolism in the brain.
Regular exercise reduces circulating levels of a protein called interleukin-6 that promotes inflammation.
The protein may also change the way in which the brain stores iron. Regular physical activity has a wide range of health benefits.
These include a reduced risk of cardiovascular disease, type 2 diabetes, various mental health conditions, and dementia.
Keeping physically active helps maintain the brain’s flexibility and improve memory. It also minimizes the decline that can occur in nerve cell growth and connectivity as people age.
Previous research in a mouse model of Alzheimer’s disease showed that exercise might even reverse some of the cognitive impairments that characterize this form of dementia.
The same scientists have now discovered that exercise may delay the progress of Alzheimer’s by changing the way the brain stores iron.
The study, which researchers at the University of Eastern Finland in Kuopio led, appears in the International Journal of Molecular Sciences.
Alzheimer’s disease, the most common form of dementia, causes the degeneration of parts of the brain that play a role in thinking, memory, and language.
Most cases are associated with age-related disease and genetic risk factors, but lifestyle factors — such as physical inactivity and a nonnutritious diet — play important roles.
Exactly how physical activity protects the brain against the effects of Alzheimer’s has been unclear, however.
One clue is that both the normal aging process and Alzheimer’s are associated with changes in the way the brain handles iron.
ResearchTrusted Source has linked the accumulation of iron in the brain and changes in iron metabolism to the formation of plaques of a toxic protein called beta-amyloid that characterize the disease.
Regular exercise can improve iron metabolism and prevent the buildup of this mineral in the brain, but the mechanisms behind this effect are uncertain.
In the new study, the scientists compared mice genetically predisposed to develop Alzheimer’s with ordinary, or “wild-type,” mice.
Half of the mice had free access to an exercise wheel in their cages, whereas the other animals led a more sedentary life.