RNA injections extend lifespan in fast-aging mice
Weekly injections starting at three weeks of age extended lifespan by 20% compared with control injections.
10 days
Limit: Lifespan effects of starting injections in old age were not measured
Stake: An author founded Milukee Therapeutics and holds shares in it.
Edited by Boris Djordjevic · AgingResearch.News
In experiments in mice, researchers used small RNA molecules packaged in fat-based particles to lower PAI-1, a protein that slows blood-clot breakdown. After initial testing in both sexes, they used male mice for subsequent experiments. Injections delivered 3 milligrams of RNA per kilogram of body weight.
One dose lowered circulating PAI-1 by 90% for 10 days. It reduced clot weight after researchers tied off a major vein in young and aged mice. Among aged mice, 83% given the targeting RNA survived four days after surgery, versus 33% given control RNA. In a separate fast-aging mouse model, weekly injections from three weeks of age extended lifespan by 20% compared with control RNA. Tests found no overt toxicity and no significant increase in blood loss or bleeding time after experimental injuries.
Why it matters
PAI-1 levels rise with age, contributing to increased clotting risk in age-related diseases. The authors propose lowering this protein as a long-lasting approach to limit its harmful effects in aging.
Caveats
The lifespan result came from a fast-aging genetic mouse model, not normally aging mice or people. The aged-mouse survival comparison involved six mice per group.
The paper
University of British Columbia
Blood, Jan 26, 2026, Open access
