Transplant Drug Delayed Aging in Elderly Mice, Shows Promise for Humans

Rapamycin, a commonly used drug for organ transplant patients, has been shown to slow the aging process in mice—even old mice—says an online report in Nature.

But this discovery was accidental.

It happened when researchers from three U.S. centers were studying the possible anti-aging effects of rapamycin on mice. During these initial studies, they found that the mice were not getting the proper dosage of the drug into their bloodstreams. They had to put the trial on hold while they put rapamycin into capsule form. By the time that they had reformulated rapamycin, however, the mice were old. The researchers decided to give these aged mice the drug anyway, and it extended their life spans—and not by a small amount. Rapamycin increased the female’s life spans by 14 percent, and the male’s life spans by 9 percent.

This is important because any other methods that had shown to slow aging in mice—such as calorie restricted diets—needed to be started early in their lives to have any positive effects.

Rapamycin is an antibiotic drug normally used to prevent organ-rejection in transplant patients. It is also used in some cancer treatments.

The National Institute of Aging sponsored the study, pulling together three research teams. These teams, according to The New York Times, “were led by David E. Harrison of the Jackson Laboratory, a mouse-breeding powerhouse in Bar Harbor, Me; Richard E. Miller of the University of Michigan; and Randy Strong of the University of Texas Health Science Center.”

Although they do not yet know how rapamycin works to slow aging, the researchers are encouraged by the results. Dr. Miller, lead researcher from the University of Michigan, believes that rapamycin could be the key to longevity—although such an anti-aging drug could take as long as 30 years to develop.

Meanwhile, researchers advise against home-experimentation with this drug. Rapamycin, marketed as Rapamune by Wyeth, inhibits the immune system and could lead to infection in humans if not closely monitored by medical personnel.