Blogs / 80beats

Researchers may have uncovered one of the universal causes of aging: A crucial type of protein that serves a double duty in organisms ranging from yeast to mice, and that becomes overwhelmed as the organism ages. The protein is charged both with repairing DNA damage and with regulating gene expression (so that, for example, a gene necessary for liver function doesn’t suddenly get turned on in the brain), and a new study has shown that when the protein is busy repairing DNA, it can’t perform its other task. Says lead author David Sinclair: “One idea of why we age is that DNA becomes damaged or mutated…. But perhaps the main culprit is the effect of genes switching on and off, and that should be reversible” [Wired News].

About a decade ago, researchers identified a protein called Sir2 that zooms to the spot of broken DNA in yeast cells and repairs the breaks. But to do that, Sir2 has to abandon its job of inactivating a sterility gene elsewhere in the yeast genome. The result is yeast cells that have intact DNA but are sterile, a symptom of aging in the fungi…. “This may be a very fundamental Achilles’ heel of life,” says Sinclair [ScienceNOW Daily News]. Now, Sinclair’s team has identified the mammalian equivalent of that protein, called SIRT1, and have determined that it plays a similar role in aging mice: When it focuses on repairing DNA damage, it neglects its gene regulation duties.

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A drug that mimics the effects of a compound found in red wine has been shown to prevent obesity and diabetes in mice that were fed a high-calorie diet and prevented from exercising, taking another step towards the target of a anti-obesity pill. The natural compound found in grapes and red wine, called resveratrol, is believed to have numerous health benefits related to longevity, heart health, and metabolism. But tests in mice suggested gallons of wine would be necessary for humans to stand a chance of getting the same benefits. The scientists turned their attention to creating a more potent drug [BBC News].

The new experimental drug, called SRT1720, was developed by the pharmaceutical company GlaxoSmithKline. Researchers explain that mice fed a high-fat diet were tricked into switching their metabolisms to a fat-burning mode that normally takes over when energy levels are low…. “We are activating the same enzymes that are activated when people go to the gym,” said Peter Elliott, a vice president at Sirtris Pharmaceuticals, the Glaxo unit that developed the drug. “That is why we believe the profile for this drug is very safe” [Reuters].

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This is the kind of medical news that always leads to people feeling happy and virtuous as they rush to the nearest liquor store. A new study has just revealed that resveratrol, a compound found in red wine, slowed down the genetic aging of middle-aged lab mice, and appeared to keep their hearts particularly young and healthy.

Of course, resveratrol is also found in grapes, pomegranates, and other foods, and medical researchers still don’t know whether the amount found in a glass of red wine has a clear effect on humans. But the report in the journal Public Library of Science ONE brings enough interesting and promising data to the table to warrant the popping of a few corks.

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