Revitalizing Old Mice: The Age-Defying Power of Young Blood

Scientists have extended the lives of old mice by connecting their circulatory systems to those of young mice, using a process called heterochronic parabiosis. The old mice lived 6-9% longer than their control peers, and their biological age was affected by the three-month blood-sharing procedure. The study measured aging using biomarkers such as the epigenetic clock, which assesses the methylation status of cytosines in DNA. The rejuvenating effect seemed to diminish over time, but the difference in lifespan persisted. The researchers speculate that the process dilutes damage in the old mice and may involve youthful factors in the blood of young mice or the detoxification of damage by younger organs.