Washington – A substance found in red wine protected mice from the ill effects of obesity, raising the tantalizing prospect that the compound could do the same for humans and may also help people live longer, healthier lives, researchers reported Wednesday.
The substance, resveratrol, enabled mice that were fed a high- calorie, high-fat diet to live normal, active lives despite becoming obese – the first time any compound has been shown to do that.
Tests found the agent activated a host of genes that protect against the effects of aging, essentially neutralizing the adverse effects of a bad diet on the animals’ health and life span.
Although much more work is needed to explore the benefits and safety of the substance, which is sold over the counter as a nutritional supplement, the findings could lead to the long-sought goal of extending the healthy human life span, experts said.
Preliminary tests in people have begun.
A long search brings hope
“We’ve been looking for something like this for the last 100,000 years, and maybe it’s right around the corner – a molecule that could be taken in a single pill to delay the diseases of aging and keep you healthier as you grow old,” said David Sinclair, a Harvard University molecular biologist in Massachusetts who led the study. “The potential impact would be huge.”
The findings triggered excitement among scientists studying aging, who hailed the findings as groundbreaking.
“This represents a likely major landmark,” said Stephen Helfand, who studies the molecular genetics of aging at Brown University in Rhode Island. “This really pushes the field forward. It’s quite exciting.”
The research, being published in today’s issue of the journal Nature, helps explain a host of observations that have long intrigued researchers, including why French people tend to get fewer heart attacks and why severely restricting the amount of calories animals ingest makes them live longer.
“This gives us hope that the idea of harnessing the power of calorie restriction is not a fantasy and can be brought to reality,” said Leonard Guarente, who studies the biology of aging at the Massachusetts Institute of Technology. “This could produce a whole new approach to preventing and treating the diseases of aging.”
Previous research has shown that laboratory animals fed very low-calorie diets live significantly longer, which has prompted some people to try strenuous “caloric restriction” diets as a possible fountain of youth, even though its effectiveness in humans remains unproven.
Testing begins
In the hope of finding a drug that could harness the natural life-extending capabilities activated by caloric restriction, Sinclair and his colleagues identified a number of promising compounds, including resveratrol, which is found in red wine, grape skins and other plants.
The compound, which increases the activity of enzymes known as sirtuins, prolonged the life span of every organism scientists have tested it on, including yeast, worms, fish and fruit flies.
To examine whether resveratrol could help mammals, Sinclair and his colleagues studied year-old mice, the equivalent of middle-age humans. A third of the mice were fed a standard diet. Another third ate the equivalent of a junk-food diet – one very high in calories with 60 percent of the calories coming from fat. The last third lived on the unhealthy diet and resveratrol.
After a year, the researchers found that both groups of mice that ate the junk food diet got fat, and those that did not get any resveratrol experienced a host of health problems, including the early signs of diabetes and heart disease. They tended to die prematurely.
But the mice that got resveratrol remained healthy and lived as long as the animals that ate a normal diet and stayed thin – adding the equivalent of 10 or 20 human years to their life span.
Moreover, the hearts and livers of the animals getting resveratrol looked healthy, the activity of a host of key genes appeared normal and they showed some of the biological changes triggered by caloric restriction. They also appeared to have a better quality of life, retaining their activity levels and agility.
“It is really quite amazing,” Sinclair said. “The mice were still fat, but they looked just a healthy as the lean animals.”
The researchers cautioned that the findings should not encourage people to eat badly, thinking resveratrol could make gluttony safe. They also noted that a person would have to drink at least 100 bottles of red wine a day or take mega doses of the available supplements to get the levels given to mice, which may not be safe in humans.
