NewScientist.com news service
A chemical found in red wine can mimic the life-extending effect of calorie-restricted diets in yeast, researchers have found.
The findings could provide a new explanation for beneficial effects of red wine. And replication of the results in mammals – although still a long way off – would raise hopes that the compound could one day be used to slow age-related diseases in humans.
“Seventy years ago we found that caloric restriction in rats increased lifespan. And over the last 70 years people have been looking for ways to explain it,” says lead researcher David Sinclair, at Harvard Medical School in the US. “Now we have shown we can control the longevity pathway with a small molecule.”
The compound is a polyphenol called resveratrol, and is found in grapes. Previous research has shown it can protect against heart disease in humans, but whether the life-extending properties it shows on yeast will extend to mammals is unknown. “It’s a long way from yeast to humans,” says David Finkelstein, at the US National Institute on Aging in Washington DC. “But it points the way to go.”
Potent polyphenol
Caloric restriction in yeast activates an enzyme called SIR2, which is thought to extend lifespan by stabilising DNA. Sinclair and his colleagues found a group of polyphenols that activated this gene in yeast and extended the organisms’ life. The most potent was resveratrol, which increased average survival time by 70 per cent.
Scientists have suggested that resveratrol acts as an anti-oxidant, mopping up harmful free radicals that damage the cell. But Sinclair found the compound does not have strong antioxidant effects in yeast.
“The lifespan enhancing properties seem to depend more on SIR2 activation,” he says. Sinclair also believes this process is responsible for the human health benefits of drinking red wine.
Unpublished preliminary results show resveratrol also extends lifespan in worms and flies, says Sinclair. But while caloric restriction, acting via the same SIR2 pathway, can cause worms and mice to live longer, no one knows this occurs in higher mammals. Primate studies are underway, but the results from the long-lived animals will not be available for years.
In the meantime, people may continue to enjoy a drink with dinner, but Finkelstein notes: “It’s silly to say that drinking a glass a day of wine a day will make you live to 150.”
Journal reference: Nature (DOI: 10.1038/nature01960)
Emily Singer
