Red-Wine Compound Might Help Prevent Cancer-Causing Sunburns, Study Finds

With summer approaching and temperatures inching higher, more people will once again feel the familiar discomfort of sunburn. And that long-term overexposure to sunlight, as dermatologists warn, can lead to skin cancer. However, new research from the University of Wisconsin-Madison indicates that a chemical compound found in red wine, resveratrol, may have the potential to help prevent sunburn and certain skin cancers.

Resveratrol is currently being tested in labs across the globe as scientists try to unlock its potential health benefits. Recent studies have indicated that the compound -- which is also found in grapes and some nuts -- might help reduce cholesterol levels, prevent some types of cancer, and reduce the growth of skin melanomas.

The researchers in Wisconsin, whose study was published in the April 15 issue of Cancer Weekly, focused on another type of skin cancer, the most widespread form, which is called nonmelanoma.

Nonmelanoma skin cancer may result from overexposure to ultraviolet radiation from the sun--particularly UVB waves. "UVB radiation is regarded as a complete carcinogen, with tumor-initiating, as well as tumor-promoting potential," the study authors wrote. It is also known to suppress the immune system and cause premature skin aging, they noted.

To test resveratrol's potential to protect skin from damaging radiation, the researchers studied 32 female mice that were born completely hairless. The skin of these mice "mimic's the human situation," especially when it comes to exposure to ultraviolet rays, according to study co-author Nihal Ahmad.

The mice were divided into four equal groups. The control group was not exposed to UVB rays and had no resveratrol applied to its skin. In the second group, each mouse had a resveratrol solution smeared on its skin, but was not exposed to UVB rays. (The solution consisted of 25 micromolars of resveratrol, a little less than what is found in a typical glass of red wine, mixed with 200 microliters of acetone.) This way, the scientists could determine if resveratrol itself could cause adverse skin reactions, such as irritation or burning.

The third and fourth groups both had beams of UVB rays shone into their cages for 12 hours, with the amount of radiation varying to reflect the changing levels of radiation in an average day. One group was treated topically with the resveratrol solution 30 minutes before UVB exposure; the other group was not given the treatment.

After the UVB lights were turned off, the scientists waited another 24 hours, then examined the mice. They measured, among other things, the skin thickness in the mice's back and ears; that provides an indication of edema, or skin swelling, coupled with the release of toxins, "which is the first response of UV exposure in humans," Ahmad explained.

The researchers also tested the epidermal layers of the skin for the presence of specific toxic enzymes associated with causing nonmelanoma skin cancer.

The mice that were covered in the resveratrol solution, but were not exposed to UVB waves, fared best -- even better than the control group -- with no increase in skin thickness and fewer of the toxic enzymes.

Among the groups exposed to UVB rays, the resveratrol-treated mice performed much better than the untreated group, with the former showing anywhere from 25 percent to 60 percent lower levels of the toxic enzymes than the latter. The burns on the resveratrol-treated mice's skin were also about one-third to half as bad.

Faring worst were the mice exposed to the UVB rays without the benefit of resveratrol. Researchers found eight times as much of one dangerous enzyme in their skin than in the control group.

Sunscreen is still the most effective preventative, according to Ahmad, although the downside is that it blocks all rays and prevents one from getting a tan. "Sun cream does not allow UV radiation to penetrate the skin," he explained, "whereas resveratrol acts as an antioxidant to prevent and repair the damages caused by UV exposure."

No one is going to be jumping in a vat of red wine before heading to the beach. But Ahmad said the future could hold a "sun cream supplemented with resveratrol" and that "resveratrol could have a therapeutic potential" for skin-cancer sufferers.

However, the experiment has yet to be conducted on humans, Ahmad noted, and similar testing on the skin of men and women could yield different results.

For a comprehensive look at the potential health benefits of drinking wine, check out senior editor Per-Henrik Mansson's feature Eat Well, Drink Wisely, Live Longer: The Science Behind a Healthy Life With Wine and The Case for Red Wine

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