This Brain-Boosting Enzyme Increases With Exercise, Researchers Say

Exercise is one of the most effective ways of promoting brain health and slowing age-related cognitive decline. Unfortunately, most people don’t get enough of it. According to the U.S. Department of Health & Human Services (HSS), only 33% of adults hit the recommended amount of physical activity.

But sedentary lifestyles may not be so much of a brain drain in the future. According to a new study published in the journal Science on July 10, there might be a way to access the brain-boosting perks of exercise without the effort.

In the study, researchers from the University of California (UC) transfused blood plasma from well-exercised mice to older sedentary mice. The result was an improvement in cognitive function along with better performances in a maze test.

After a thorough investigation, the researchers narrowed down this remarkable effect to a single enzyme called GPLD1, which increases with exercise.

To corroborate their findings, the UC researchers examined a group of patients at the UCSF Memory and Aging Center. After tracking the physical activities of the patients with Fitbit devices, researchers observed that the more active participants produced more GPLD1. Elevated GPLD1 was associated with better cognitive performance in humans too.

Although the mechanisms behind this enzyme are yet to be fully understood, the UC study confirms how important exercise is in preventing cognitive decline. It could also spawn more research that leads to breakthrough medicines for Alzheimer’s and other neurological diseases.

Exercise and Brain Health: What We Know So Far

At the most basic level, physical movement increases heart rate and improves the flow of blood and oxygen to the brain. This improved circulation has been linked to enhanced cognition.

In a 2014 study published in the journal Clinical Interventions in Aging, exercise was shown to promote the growth of certain brain regions (such as the hippocampus) that promote learning and memory-retention. In another study conducted by researchers from the Rush University Medical Center, active adults retained their cognitive function for longer than less active adults—even when the active group had biomarkers related to dementia.

How Do We Get More GPLD1?

The liver produces more of the GPLD1 enzyme when a person exercises. According to the new UC study, there was more nerve growth in the brains of older mice when GPLD1 was elevated, which led to a better performance in the maze. But there are other factors involved.

“This enzyme also appears to work by decreasing inflammation and oxidative stress,” Sommer Ebdlahad, MD, a board-certified neurologist at Virginia Spine Institute, tells Verywell. Inflammation and oxidative stress are known culprits of age-related brain damage.

The results of the UC study have evoked dreams of an "exercise pill" from physicians and biohackers around the world. But experts say that much more data is needed to determine if these benefits will transfer to humans—especially to the aged and diseased populations who might need these benefits the most.

 “This GLPD1 theory has only been looked at in the context of healthy aging,” says Sarah McEwem, PhD, NSCA-CP, director of research and programming at Pacific Neuroscience Institute in California, tells Verywell. She says that the media should be cautious about extrapolating the UC study results for diseases such as Alzheimer's, where there is “significant neurodegeneration due to cell loss.”

There are practical issues that need to be considered as well, such as that of digestion.

GPLD1, a protein by definition, might not make it into the blood stream after it contacts stomach acid. But even if the researchers figure out a way to package this enzyme into a pill, approving it for public use is going to take a while.

“On average, it takes about 10 years for a new compound or therapy to complete the development, clinical trials, and approval stages,” McEwen says.

Will This Mean the End of Exercise?

If you’re dreaming of the day you’ll finally break up with your dumbbells, that may never happen. And the reason is simple: Exercise does so much good for the mind and body that it’s impossible distinguish just one component that does the trick.

Ebdlahad stresses that the benefits of exercise extend beyond memory.

So if a GPLD1 pill is eventually produced, you’ll reap the most benefits by taking it in addition to some level of exercise. Healthcare providers typically recommend 30 minutes of moderate exercise per day.