all David A. Sinclair stories

Harvard researchers find longevity, restricted diet link

404132862 — Thu, 20 Sep 2007 15:17:33 -0400

Researchers believe they’ve found the cellular link between extremely restricted diets and dramatically lengthened lifespan and hope to use the knowledge to develop new treatments for age-related diseases.

The research, conducted by scientists at Harvard Medical School, Cornell University Medical School, and the National Institutes of Health, illuminates for the first time the cellular processes triggered by extremely low-calorie diets.

Scientists have known for about 70 years that extremely restricted diets — where caloric intake is 30 percent to 40 percent below normal — can extend lifespan by as much as a third. In addition, those years are healthier and relatively free of common age-related debilities such as cancer, heart problems, and type 2 diabetes.

Wine molecule slows aging process

70652986 — Mon, 26 Mar 2007 05:30:12 -0400

Called resveratrol, a wonder substance discovered by Harvard researchers seems to work in the same way as does drastic calorie cutting. Dramatic reduction of calories has been shown to increase the life span of mice, rats, and monkeys. Such diets are being tried in humans but results are not yet in. Severe dieting also cuts the risk of dying from cancer, heart problems, and other age-related diseases in monkeys. If resveratrol and related molecules are found to work as well in humans, we could gain extra years of healthy life without starving for them. We could have our cake and eat it, too. "The discovery brings closer a time when a drug that extends life and prevents many diseases of aging becomes a reality," says David Sinclair, who leads the research at Harvard Medical School. "I'm not a doctor so I can't speculate on how much wine to drink, but I've increased my consumption since we made the discovery." Physicians recommend a glass or two of red wine a day as part of a heart-healthy diet. No one would advise nondrinkers to starting gulping red wine until better information about its anti-aging effect becomes available.

Eating less and living longer

70652986 — Mon, 26 Mar 2007 05:29:01 -0400

Tantalizing evidence exists that cutting calories by 20 percent helps monkeys, who are close relatives, to live longer, healthier lives. And, in one nonscientific program, adults are reducing their caloric intake by as much as 30 percent in the hope of living healthfully (if not too happily) for 100 years or more. What if scientists can figure out just what combination of genes and proteins extends the lives of so many other living things that don't fully give in to their hunger? In that case, it might be possible to come up with drugs that would let us have our cake and eat it, too. David Sinclair and his colleagues at Harvard Medical School have cooked up some delicious clues to how this might happen. They found an enzyme that makes yeast cells live longer simply because they think they are starving. The enzyme catalyzes a marked increase in the activity of a protein known as Sir2, which in turn promotes yeast survival by reducing events associated with cell death. With the help of the enzyme, called Pnc1, yeast cells live 70 percent longer. If humans lived that much longer, their average life span would increase from 80 to 136 years. Humans aren't yeast, or worms, flies, or rats, but they do have a version of Sir2 called SIRT1.

New molecular model increases longevity and could allow you to eat cake, too

70652986 — Mon, 26 Mar 2007 05:21:25 -0400

Scientists have known about the longevity benefits of caloric restriction since experiments in the 1930s showed that rats lived much longer if their food intake was severely restricted. Broadly speaking, the reason is stress. Although usually viewed as the enemy of good health, stress can actually boost longevity, driving an organism to slow down metabolism and conserve scarce resources. Caloric restriction is one form of stress that does this very effectively. But to see the longevity benefits, animals must eat only about half the calories in a normal diet, resulting in constant hunger. Now, Harvard Medical School researchers have discovered a way to genetically mimic the life-extending effects of calorie restriction -- without the severe food deprivation that method entails. The findings might someday lead to drugs that give people longer, healthier lives. Previous studies have shown that a key component in the longevity pathway is the Sir2 protein, "one of the most exciting molecules in aging research," says David Sinclair, Harvard Medical School assistant professor of pathology, and senior author of the new research. The research appeared in the May 24, 2002, Journal of Biological Chemistry.

Cancer cells' immortality may depend on longevity protein

70652986 — Mon, 26 Mar 2007 05:10:38 -0400

A team of Harvard Medical School researchers has identified a protein that 10 percent of tumor cells use to attain an immortal state. By blocking the molecule, it may be possible to stop these cancer cells from proliferating. The approach might also be used as part of a two-pronged strategy to combat the remaining 90 percent of tumors, the researchers say. "This gives us a new drug target for cancer," said David Sinclair, Harvard Medical School assistant professor of pathology. He and Haim Cohen, HMS research fellow in pathology, published their findings in March 2001.