A new study may explain why some diabetes and weight-loss drugs are showing early promise in protecting the brain. It all comes down to how our brain cells handle sugar.
Scientists at the Buck Institute for Research on Aging have discovered that neurons — the cells that keep your brain working — don’t just burn sugar for energy. They also use it to protect themselves from damage. And when that sugar-clearing system breaks down, it may open the door to diseases like Alzheimer’s.
The research, published in Nature Metabolism, looked at both fruit flies and human brain cells affected by tau — a protein that builds up in Alzheimer’s and other types of dementia. The team found that in diseased cells, sugar called glycogen builds up and gets stuck, which prevents the cell from breaking it down and using it for protection.
When the researchers helped the cells re-activate a sugar-clearing enzyme, the brain cells were able to reduce protein damage and defend themselves from oxidative stress — the kind of internal wear-and-tear that speeds up aging.
Even more exciting? Dietary restriction — known to slow aging in animals — naturally turned on this same sugar-clearing system. And a drug that mimics those effects also worked. This may explain why GLP-1 drugs, like those used for diabetes and weight loss, have recently shown brain health benefits in clinical studies.
The findings were also confirmed in brain cells from people with frontotemporal dementia, suggesting this sugar management system could be relevant across multiple forms of cognitive decline.
Researchers say this opens a new path forward in the fight against Alzheimer’s. Instead of focusing only on toxic proteins, they’re looking at how cells protect themselves and how diet, medication or lifestyle changes might support those defenses.
The study was supported by the NIH, Hevolution Foundation, Larry L. Hillblom Foundation, American Federation of Aging Research, and others. Lead author Dr. Pankaj Kapahi is a researcher at the Buck Institute and an advisor to Juvify Bio, a company focused on healthy aging.