An experimental nasal spray developed by Texas A&M researchers improved memory and reduced signs of brain inflammation in aging mice, according to a new study. The finding could help guide future research into dementia and age-related cognitive decline.
The study, published in the Journal of Extracellular Vesicles, tested two doses of a nose-delivered therapy in 18-month-old mice, an age the researchers described as roughly comparable to a 60-year-old person. The treatment used extracellular vesicles, tiny particles released by cells, derived from human neural stem cells. Researchers said mice that received the treatment later performed better on memory tests than mice that received a control treatment. Their brains also showed lower levels of inflammation and oxidative stress in the hippocampus, a region involved in memory.
While the treatment is not available for people and has not yet shown that it works in humans, the Texas A&M team said the treatment appeared to affect several inflammatory pathways associated with aging brains, including NLRP3 and cGAS-STING signaling. The study also found changes tied to mitochondrial function, which affects how cells produce and use energy.
Dr. Ashok K. Shetty, a university distinguished professor at the Texas A&M University Naresh K. Vashisht College of Medicine, said the work points to a possible way to target brain aging without surgery or direct brain injections.
“Our approach redefines what it means to grow old,” said Shetty. “We’re aiming for successful brain aging: keeping people engaged, alert and connected. Not just living longer, but living smarter and healthie.”
The study focused on “neuroinflammaging,” a term used to describe chronic inflammation in the brain that can increase with age and has been linked to cognitive decline.
Researchers gave late-middle-aged mice two intranasal doses of extracellular vesicles two weeks apart. The animals were later tested on tasks meant to measure recognition memory and the ability to detect changes in object location.
The mice that received the treatment showed improved cognitive and memory performance, according to the study. Researchers also found fewer signs of inflammatory activity in brain immune cells called microglia.
“We are seeing the brain’s own repair systems switch on, healing inflammation and restoring itself,” Shetty said.
The findings add to a growing area of research into how inflammation contributes to aging and neurodegenerative disease, but the study was conducted in mice. More work would be needed to test safety, dosing, long-term effects and whether the approach works in larger animals or humans.
The research team has filed a U.S. patent for the therapy, according to Texas A&M. The study was supported by the National Institute on Aging.