An Enzyme That Increases With Exercise Can Improve Memory In Mice, And Maybe People

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Mice that exercise produce more of an enzyme that can improve memory and other brain functions.





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A Single Protein May Help Explain Memory Loss In Old Age

The scientists then narrowed their search to about a dozen proteins in the blood. One in particular, an enzyme called GPLD1, seemed to be key. When scientists revved up the production of this enzyme in older mice, nerves grew in part of their brains, and the animals performed better in the maze.

«Exercise causes this protein to be produced in the liver, Villeda says. And among other things, when this enzyme enters the bloodstream, it seems to tamp down aspects of inflammation, which contributes to age-related brain damage. «The result of that is that you actually have improvement in cognitive function in these older mice.

The research team also looked at a group of older people at the UCSF Memory and Aging Center. Researchers measured their physical activity with Fitbits. Those who exercised more produced more of this enzyme.

Aging and exercise are both complicated, involving all sorts of variables that interact in unexpected ways. So Villeda had to think hard about whether a single protein could really have a big effect.

«I was definitely surprised that one protein could have that much effect, he says. But when he realized GPLD1 is changing about 100 other proteins, it seemed plausible.

Scientists are nowhere near understanding the complex relationship among all these interacting parts.

«It’s a long step between identifying this enzyme and, say, making a pill out of that, says neuroscientist Bradley Wise at the National Institute on Aging. But he finds the results intriguing — and in keeping with a line of research his institute is actively encouraging. «This is one piece of the puzzle.

The team at UCSF is eager to see if it can find its way to making a medication out of its now-patented discovery. Villeda says the discovery at least suggests a path forward.

«We don’t have that exercise pill right now, he says. «This lets us know that this is a viable thing to pursue, but we’re not there yet. My mom gets really excited — she [says], ‘Oh, exercise in a bottle!’ «

But that is not around the corner. «I wouldn’t rush out and make GPLD1 and give it to people, says Willard «Bill Freeman at the Oklahoma Medical Research Foundation and the Department of Veterans Affairs medical center in Oklahoma City. Freeman co-wrote a commentary about the paper for Science.

He’s encouraged by the new findings but cautions that almost nothing is known about the potential downsides of tinkering with this enzyme and the complicated system it affects.

«There’s a lot more research to be done. And in the meantime, one of the things we can all do is exercise. We have that within our own power.

Exercise has all sorts of health benefits beyond the brain, from strengthening bones to helping control blood pressure. So if this discovery ever does lead to a medication, it would be most helpful for people who, through injury or old age, simply can’t exercise on their own.

You can contact NPR science correspondent Richard Harris at .


Correction July 9, 2020

A previous version of this story included a photo of a gerbil that was mislabeled as a mouse.