There is a study going on in Seattle that has scientists transfixed on a group of 20 dogs. The dogs are all house pets and older than six years old and are early test subjects in a trial for a drug that has lengthened the life spans of worms, fruit flies, and mice. The drug, called Rapamycin, has been used for years to prevent rejection of transplanted organs. If the drug works on dogs, it could be tested on healthy human volunteers.
Scientists aren’t sure why the drug can suppress the immune system in some ways and boost it in others. They are only starting to learn how it might slow the aging process.
The drug is not without side effects. At high doses, Rapamycin can raise the blood sugar and increase the chance of diabetes. It can also cause mouth lesions known as canker sores.
Rapamycin is just one drug that appears to slow aging in animals by triggering the same biochemical pathway. The whole idea is in trying to trick the body into acting as though it’s running out of energy and then the body has to put more effort into long term survival, says David Sinclair, a Harvard Medical School researcher.
The drug is named after its origins on Easter Island, where it was originally isolated from soil bacteria and named after the island’s native name, Rapa Nui. It is one of five drugs that have lengthened the lives of mice in test studies. With that being said, it is most likely easier to obtain life extension in mice more than in people.
Steven Austad, a researcher at the University of Alabama-Birmingham, has studied several species in an attempt to figure out why some mammals such as whales can live up to 200 years, but when it comes to mice they may only live for a couple of years. Small mammals tend to have shorter life spans than larger ones, as it seems evolution has optimized them for reproduction.
Scientists are optimistic about Rapamycin because it has already extended mouse life spans by 9 to 14 percent and seems to work whether mice started taking the drug during middle age or later in their short lives. The drug also prevented cardiovascular damage and memory loss. It may be a good sign that the drug lengthens the time that people are healthy and functional rather than being in a period of decline.