Cathepsin-B as a Promoter of Brain Function
by Daniel Schneider
At this point in time, there is no lack of physiology research that shows the benefits of exercise. But that will not stop us from continuing to point out new and exciting research for our readers. Today we discuss a potential mediator of brain and memory health that is improved through exercise.
The basic understandings of the benefits of exercise are related to training adaptations. Essentially, exercise trains your heart to better handle stress, and trains your cells to efficiently utilize sugars. However, our understanding of myokines is broadening our understanding on how exercise benefits diverse parts of the body and various disease processes. You may remember that we classified IL-6 as a myokine in a blog just under a year ago.
Enter Cathepsin-B (CTSP), a myokine that is associated with brain health. Recent research in Cell elaborates on the effects of this CTSP by testing for elevated CTSB levels in stimulated muscle samples, testing the effects of exercise on CTSB levels in mice, and testing the effect that CTSB had by comparing exercised mice to exercised mice who are unable to produce this myokine.
The researchers found that exercised muscle produces CTSB, and that CTSB improved the expression of brain derived neurotrophic factor, a compound that stimulates new nerve growth in the hippocampus of the brain. The hippocampus is the part of the brain that helps humans synthesize short-term memories, ultimately helping us remember where we left our keys. In mice, we test this by testing their spatial memory… typically seeing how fast they can find their way through a maze.
Today’s study of interest found that exercised mice that were made unable to produce CTSB did not receive the same benefits, as seen through hippocampus nerve growth and spatial memory, as mice who were able to produce CTSB. And while interventional studies in humans won’t start anytime soon, we clearly know that exercise does increase the plasma levels of CTSB in humans too.