Bioethics Blogs

Creative Minds: The Muscle-Brain Connection

Muscle activity and brain functionThere’s mounting evidence that exercise has a powerful effect on the human brain. For example, many studies have shown that physical activity appears to reduce the incidence of depression. Exercise can also delay or possibly even prevent Alzheimer’s disease, as well as easing symptoms in people who have these disorders [1, 2, 3, 4, 5]. But how, exactly, does getting our legs moving and our hearts pumping exert a positive influence on our brains?

Two scientists at Stanford University School of Medicine are out to get some answers to this important question. They have proposed that when we exercise, our muscles secrete a factor or combination of factors into the bloodstream, leading to structural and functional changes in the brain.

Winners of a 2013 NIH Director’s Transformative Research Award, Tony Wyss-Coray and Thomas Rando plan to collect all of the molecules that muscles secrete that enable them to communicate with other cells. These molecules include hormones, growth factors, and small proteins called cytokines that are important in cell signaling. The Stanford duo suspects that the key to exercise’s beneficial impact on the brain may lie in its effect on this collection of molecules—which they have dubbed “the communicome.”

To study the communicome, Wyss-Coray and Rando will use a technique called parabiosis to couple the circulatory systems of physically active mice with mice that are less active. If the “couch potato” mice benefit from the blood of the active mice, then the team will analyze the blood to find the responsible factor(s).

This is definitely high-risk high-reward research.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.