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SPECIAL SUMMER ISSUE: A DAY AT THE BEACH

Protection turned inside out

Sunscreen and smarts still rule, but `morning-after' cellular repair and burn-prevention pills are coming along.

May 28, 2007|By Shari Roan | Los Angeles Times Staff Writer
  • BEYOND SUNSCREEN: Some new sun protection products fall into two categories: those that help repair cellular skin damage and those that make the skin less sensitive to the sun.
BEYOND SUNSCREEN: Some new sun protection products fall into two categories:… (Anne Cusack / Los Angeles…)

Constant worrying about the sun and its power to burn, wrinkle and mottle the skin -- or worse, cause cancer -- comes with the summer territory. But what if there were an extra level of protection, say a pill or a lotion, that helped prevent the most common effects of too much ultraviolet light?

Researchers are working on it.

"Sunscreens are difficult to use properly," says Daniel Yarosh, president of AGI Dermatics, a Freeport, N.Y., biotech company that is developing a lotion to help the skin mend itself. "Science is trying to find something better."

The beyond-sunscreens research falls into two categories. One approach helps repair cellular skin damage after too much sun exposure. The other approach makes the skin less sensitive to the sun.

"The research in this field is still relatively early," says Dr. Henry W. Lim, chairman of the department of dermatology at Henry Ford Hospital in Detroit. "But I think this is something that will continue to develop."

Repair from within

The most rigorously tested damage-control product thus far is called Dimericine, developed by AGI Dermatics.

Currently in stage-three clinical trials, the product is based on an understanding of how cells try to repair themselves when damaged.

"The idea that people can have a natural repair mechanism is known," Yarosh says.

"What is new is that there are things we can do to optimize it. We're moving into a stage of understanding how the cell responds to damage -- what genes get turned on in young skin and what genes get turned on in old skin and how can we make old skin act young.

"That's what makes this so exciting."

Dimericine, he says, contains a customized enzyme that can recognize DNA damage caused by ultraviolet light and speed up repair.

"It's like patching a tire," he says. "You can get rid of the damage and the DNA goes back to being normal.

"We call it a morning-after lotion. It can be used after sun exposure but before damage has arrived."

The company is testing the product, which would be available only by prescription, in people with a condition called xeroderma pigmentosum, a rare genetic disease that predisposes individuals to skin cancer. A study of 30 people published in 2001 in the Lancet showed the lotion reduced the incidence of precancerous growths, called actinic keratoses, by 68% and basal cell carcinoma by 30%.

FDA approval, which is unlikely before 2010, would mean that the estimated 58 million Americans with precancerous skin lesions and others at high risk for skin cancer could benefit, Yarosh says.

"If indeed this is shown to be beneficial in otherwise healthy individuals, it would obviously be a very exciting development in this field," says Lim, who is not involved in the product's development.

AGI Dermatics also makes an over-the-counter product that purports to help repair DNA-damaged skin cells. Called Remergent, it uses botanical extracts to help stimulate the normal repair mechanism to prevent wrinkles and other cosmetic effects of sun damage.

Protection in a pill?

Meanwhile, several supplement manufacturers are touting sunburn-prevention pills they say can protect the skin by limiting reaction to the sun. The best known is Heliocare, which contains the antioxidant polypodium leucomotos, an extract from a fern that grows in South and Central America.

The substance is thought to decrease the body's sunburn reaction.

Normally, when ultraviolet light reaches the cells, it creates free radical molecules -- high-energy molecules that damage the proteins and lipids in the cell and eventually lead to photo-aged skin. Polypodium leucomotos appears to help inactivate free radicals before they can damage cells.

"There are quite a number of studies published in the peer-reviewed literature -- although in small numbers of subjects -- to show this product would decrease the ability of the skin to be sunburned, decrease the ability of the skin to tan and the DNA damage that would occur following exposure to the sun," Lim says.

Other oral antioxidants may also work in a similar manner. Several companies market a supplement containing astaxanthin, a chemical that produces the red coloration in several species of marine life, such as salmon and shrimp. Although trials have been limited, a 2002 study in the Journal of Dermatological Science found that astaxanthin reduced the effects of UVA radiation in cells in a lab culture.

One maker of astaxanthin supplements says that the company began studying the compound for sunburn protection after customers who were taking it for other reasons began reporting that they didn't burn as easily.

"I think more research needs to be done on this. But the initial research is encouraging, and the anecdotal research is encouraging," says Gerald Cysewski, president of Cyanotech, a Kona, Hawaii, supplement manufacturer that makes an astaxanthin product called BioAstin.

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