GLP-1 Drug Semaglutide Extended Lifespan in Older Mice in NIH Study

Semaglutide Lengthened Median Lifespan in Older Mice

Semaglutide extended the median lifespan of older healthy female mice by nearly 100 days in a study funded by the National Institutes of Health (NIH). Researchers at the University of California, Berkeley (UC Berkeley) administered the glucagon-like peptide-1 (GLP-1) receptor agonist to 20-month-old mice to evaluate physical function and survival late in life.

The treated animals showed improvements in muscle strength, cognitive performance, and blood sugar regulation compared with untreated controls. Analysis of gene activity showed lower inflammation markers and preserved tissue repair mechanisms.

Effects Diverged from Standard Calorie Restriction

Semaglutide produced physiological changes that differed from standard dietary restriction despite similar reductions in food intake. To isolate whether reduced food intake drove the benefits, the team compared mice given semaglutide against animals on a 24 percent calorie-restricted diet for five months.

Mice receiving semaglutide showed gains in exploratory behavior and spatial memory above baseline levels. The resting metabolic rate in the semaglutide group stayed stable, whereas the metabolism of calorie-restricted mice slowed down.

Biological Pathways Driving Metabolic Resilience

Metabolic stability during weight reduction indicates that GLP-1 receptor signaling may engage longevity mechanisms independent of simple energy deficit. Lead author Danica Chen, Ph.D., noted that identifying these specific signaling routes could inform future interventions for age-related decline.

Rafael de Cabo, Ph.D., a senior investigator at the National Institute on Aging (NIA), noted in an accompanying commentary that chronic conditions often stem from biological aging. Interventions that moderate age-associated decline could therefore alter risks across multiple organ systems at once.

Human Longevity Trials Remain Uncompleted

Rodent longevity outcomes cannot confirm whether semaglutide or other GLP-1 medications alter biological aging or survival in humans. Clinical evidence in people currently centers on metabolic parameters, including a recent secondary analysis of the SLIM LIVER trial.

Researchers have not yet tested semaglutide specifically for lifespan extension in healthy older adults. Anyone evaluating GLP-1 therapies for blood sugar control or weight management should discuss documented indications and known adverse effects with a personal physician.