Monday, July 11, 2016
Worried about losing your memory--exercise may be key
An NIH-funded study identified a biochemical, a protein called cathepsin B (beta), that rises in the blood of people who exercise regularly. In mice, this same protein was associated with the production of new brain cells called neurons. Mice unable to produce this protein did not experience a boost in memory.
Published in Cell Metabolism, the study set out to find proteins that muscle cells produce that could be transported to the brain. This produced a short list of possibilities. But one stuck out--this cathepsin B.
They also determined that this one was able to cross the blood-brain barrier--which blocks proteins that are too big or have the wrong biochemistry. And when it crossed, genes were expressed consistent with the growth of new brain cells.
Then the switched from mice to humans. They looked at 40 healthy young adults in Germany, ages 19 to 34, equally divided between men and women.
Regular fitness training showed an increase in cathepsin B. These subjects also showed better visual memory.
In mouse models, cathepsin B levels have been neuroprotective--delaying the onset of Alzheimer's.
Many questions remain. For one thing, what do those new neurons amount to?
Still, exercise has other benefits, too--so why not if you can?