A hormone released during exercise may protect the brain against Alzheimer’s disease, research suggests.
Irisin is a messenger protein generated by muscle tissue that is carried around the body in the bloodstream.
The new evidence indicates that it may be behind the known positive effects on mental performance of taking exercise.
US and Brazilian scientists found lower levels of the hormone in the brains of Alzheimer’s patients compared with healthy individuals. The same was true for the precursor protein from which irisin is derived, FNDC5.
In tests on genetically engineered mice, the scientists induced learning and memory deficits by cutting out irisin.
They were able to reverse these effects by restoring the hormone.