Gene therapy extended lifespan with health benefits in mice
Male mice treated at 13 months had a median lifespan of 33.92 months, compared with 28.14 months in controls.
Limit: The experiments used only one mouse strain
Edited by Boris Djordjevic · AgingResearch.News
In an animal experiment, researchers tested muscle-directed gene therapy in aged and geriatric male and female C57BL/6J mice. They used a viral carrier to deliver the gene for fibroblast growth factor 21, a protein called FGF21, into hindlimb muscles. Overweight, insulin-resistant males treated at 13 months received 3 × 10¹¹ viral genomes. Controls received a carrier without the FGF21 gene.
The treatment extended health span—the period of life in good health—as well as lifespan. Treated mice showed better blood sugar control and muscle performance. Memory improved in old males, while old females also showed cognitive benefits. The treatment preserved the liver’s detoxification capacity, counteracted age-related kidney disease and promoted heart health. Tissue analyses indicated improvements in energy balance and reduced inflammation.
Why it matters
Declining organ function limits healthy life during aging. The authors identify FGF21 gene therapy as a potential strategy to delay deterioration across multiple organs.
Caveats
These were experiments in one mouse strain, not tests in people. The detailed lifespan comparison came from overweight, insulin-resistant males treated at 13 months.
The paper
Universitat Autònoma de Barcelona
Molecular Therapy, Jun 2, 2026, Open access
