First of all, no one is suggesting that if you suffer from depression and anxiety, you should drink a lot of red wine. That would ultimately not help the situation. However, it turns out that a plant-derived compound in the wine – known as resveratrol – could indeed make a difference.

A phenol found in the skin and seeds of grapes and berries, resveratrol was already known to have an antidepressant effect. The means by which it works, however, was not fully understood.

In order to find out, scientists from the University of Buffalo and China's Xuzhou Medical University turned to experimenting on mice. Among other things, they discovered that an enzyme known as phosphodiesterase 4 (PDE4), which is expressed by the stress-response hormone corticosterone, caused depression- and anxiety-like behavior in the animals. It did so by lowering levels of a messenger molecule called cyclic adenosine monophosphate.

Ordinarily, corticosterone regulates the body's response to stress. When there's too much stress, though, the large amounts of the hormone circulating in the brain lead to an excess of PDE4. This in turn physically alters the brain, causing the problems.

Upon administering resveratrol to the mice, the team found that the compound kept the rodents' corticosterone from expressing PDE4. As a result, they appeared to be considerably less depressed and anxious upon being stressed.

It is now hoped that resveratrol could find use in a new class of antidepressants. Most such medications currently work by controlling serotonin or noradrenaline function in the brain, although according to the scientists, only about one third of patients taking them end up in full remission.

"Resveratrol may be an effective alternative to drugs for treating patients suffering from depression and anxiety disorders," says U Buffalo's Dr. Ying Xu, co-lead author of a paper on the study.

Previous studies have indicated that resveratrol may also help fight obesity, aging, cavities, and muscle loss.