The most-senior mouse in the study was Ike, the namesake of a relative of one of the researchers. The mouse Ike lived 1400 days. For a person, that would be like hailing a 140th year birthday.
Rapamycin, approved by the Food & Drug Administration for certain organ transplant recipients, is already known to extend life in mice and delay some age-related problems in rodents and humans.
Still, many questions prevail about when, how much and how long to administer rapamycin, what its mechanisms of action are in promoting healthy aging, and ways to avoid serious side effects.
Scientists at the University of Washington, University of Missouri, and Fred Hutchinson Cancer Research Center explored some of these issues.
Research showed that a transient dose of rapamycin in middle age was enough to increase life expectancy and improve measures of healthy aging. The scientists treated mice with rapamycin for 90 days. The treatment was started at 20 months of age, approximately the mouse equivalent of a 60 year old person.
The control mice and the rapamycin-treated mice were maintained identically both before and after the treatment period. Remarkably, the rapamycin treated mice lived up to 60 percent longer after the treatment was stopped, compared to the animals that received a mock control treatment.
This, the researchers said, seems to be the biggest increase in life expectancy ever reported in normal mice from a medication. The mouse Ike lived 1400 days. For a person, that would be like hailing a 140th year birthday.