Virginia Tech neuroscientist Timothy Jarome announced on June 15 that he is investigating whether obesity may accelerate the brain's aging process, potentially contributing to earlier memory decline. The research aims to clarify how obesity increases the risk of dementia and Alzheimer's disease, a connection scientists have long recognized but not fully understood.
Jarome, a professor in the College of Agriculture and Life Sciences' School of Animal Sciences, studies molecular mechanisms behind memory disorders such as dementia, Alzheimer's disease, and post-traumatic stress disorder. His latest research is supported by a $410,000 grant from the National Institute on Aging.
The stakes are significant: about one in three adults over 70 experiences age-related memory loss—a condition with no treatment—while nearly 40 percent of U.S. adults are obese. Jarome said that if both conditions are driven by the same pathway in the brain, it could reveal new targets for treatments designed to slow memory loss and reduce dementia risk.
In previous work, Jarome's team found that a molecular process called K63 polyubiquitination becomes more active as memory declines. In younger brains, K63 levels drop during learning to help memories form; in older brains, those levels remain high instead of adjusting normally. Lowering K63 levels using targeted gene-editing improved memory in older rats. A similar pattern was observed when young rats were fed a high-fat diet: they showed elevated K63 levels comparable to much older rats and performed worse on memory tests.
"What surprised us was we were seeing the same changes in young obese rats that we normally see in much older brains—just on a much faster time scale," Jarome said. "It suggested that obesity-induced memory loss and age-related memory loss may be directly connected through this pathway." The new study will follow rats fed either a high-fat or normal diet from young adulthood through old age while tracking changes in their memories and related proteins.
Researchers will also use CRISPR-based tools to reduce K63 levels before obesity develops to determine if improving this process can prevent or slow down related memory decline. "If we can understand the mechanism that connects these two things, then we can start thinking about ways to target it," Jarome said. "My hope is that this will help us better understand what's causing the brain to essentially age faster and make us more likely to have dementia and Alzheimer's disease."
