Metformin, a drug widely used to treat type 2 diabetes, may act on several biological mechanisms of aging at once and could extend healthy lifespan, scientists reported in a review published in the journal Aging.
How the drug may work
The review's authors combined results from decades of research on metformin conducted in cells, animals and humans. According to the review, the drug activates a protein called AMPK, which responds to energy shortages in cells and triggers processes of cellular repair and autophagy, the mechanism by which cells clear out damaged components. Metformin may also affect DNA stability, chronic inflammation and the composition of the gut microbiome, the authors said.
Metformin has been prescribed for type 2 diabetes for decades because it lowers blood sugar levels, and it remains one of the most commonly used diabetes medications worldwide. Researchers have increasingly studied it separately for its potential effects on aging, since AMPK activation is one of the pathways linked to cellular longevity.
Findings in animal studies
In experiments on nematode worms, metformin increased lifespan by 36 to 40 percent, the review noted. In various studies on mice, the drug extended lifespan by an average of 5.8 to 20.1 percent, depending on the study.
In male monkeys given the drug for 40 months, scientists had previously found signs of a reduction in the biological age of tissues. By some measures, the biological age of the brain decreased by almost six years, according to the earlier findings cited in the review.
Mixed results in humans
Observational studies in humans have also linked metformin use to a lower biological age, the review's authors said. However, they cautioned that the results of such studies remain inconsistent.
For now, the authors consider metformin a promising candidate for further study as a potential drug against age-related changes, rather than a proven anti-aging treatment.
What comes next
The review follows earlier research in which scientists found that semaglutide, a drug used for diabetes and weight loss, may also extend lifespan and weaken age-related changes in the body, according to the article.
