Easter Island soil drug 'makes mice live longer'
Scientists in the US say they are a step closer to extending life expectancy after three studies found that a drug called rapamycin is capable of increasing the longevity of mice.
The drug, discovered in a soil sample from Easter Island in the 1970s, has already shown benefits in treating a variety of medical conditions.
In tests on middle-aged mice of about 20 months old, the drug increased life expectancy by up to more than a third.
Arlan Richardson, director of the Barshop Institute responsible for one of the experiments, says this is the first demonstration that there might be an anti-ageing pill available in the future.
"What they've shown here is that for the first time it's possible to use a drug or a single compound and feed it to a mammal, a mouse, which is fairly similar to human beings, and these mice will live longer," he said.
The discovery could have major implications for society, particularly in the treatment of age-related diseases such as cancer, heart disease and perhaps even neurodegenerative diseases like Alzheimer's and Parkinson's.
Dr Richardson suggests that clinical studies examining the feasibility of rapamycin in treatments could be imminent.
"I know that there are studies ongoing now in using rapamycin in cancer treatments and therapies," he said.
University of Washington biochemist Brian Kennedy says that if the claims are true then it would be a big step in medical research.
"If there's a drug that can slow the rate of ageing it will provide a protective mechanism against a whole range of these different diseases," he said.
"That remains to be shown, but we're getting to the point in ageing research where we can directly test this idea."
The down side
But rapamycin has potential negative side-effects which could preclude its use in humans.
"What we don't know is whether long-term chronic exposure at low doses, which is what the mice were given, will give rise to these negative effects as well," Dr Kennedy said.
"But I think it is exciting because it's the first drug that offers that potential down the road.
"I think there'll be more drugs coming that have similar affects. The key will be finding the right ones that give you the benefits and don't have the negative consequences."
Anti-ageing drugs have their critics, and Dr Richardson says he can understand why people are sceptical.
"I would have been one of those sceptics about a year ago, or even six months ago. I've been involved in ageing research for about 30 to 35 years, and about every couple of years there's something that's touted will slow down ageing," he said.
"I had assumed that we would not find a drug or a compound that would do it in my lifespan, but this is probably the best controlled study, it was done at three sites and they replicated it at all three sites."
By Kathryn Stolarchuk
July 09, 2009