Dermatologists Can Help Patients Choose New Topical Treatments for Aging Skin
NEW YORK, Oct. 23 /PRNewswire/ -- Each year, Americans trying to recapture their youth spend billions of dollars on skin care products claiming to rejuvenate the skin. Most of these over-the-counter skin care products are coined "cosmeceuticals," which are a cross between a cosmetic and a drug. Do these products actually work? Dermatologists who study cosmeceuticals think the answer lies in the ingredients and how they interact with the biological mechanisms that occur in aging skin.
Speaking today at the American Academy of Dermatology's Derm Update 2002, dermatologist Patricia Farris, MD, Clinical Assistant Professor at Tulane University School of Medicine in New Orleans, Louisiana, discussed the newest anti-aging skin care products and the science behind them.
Considerable research has been done to understand the aging process. With aging, all skin cells begin to produce excess amounts of free radicals. Free radicals are unstable oxygen molecules which, under ideal circumstances, are removed by naturally occurring anti-oxidants within the skin's cell.
In aging skin cells, naturally occurring anti-oxidants are in short supply. The free radicals generated are left unchecked and cause damage to cell membranes, proteins, and DNA. These free radicals eventually break down collagen and release chemical mediators that cause inflammation in the skin. It is a combination of these cellular and molecular events that leads to skin aging and the formation of wrinkles.
"Since naturally occurring anti-oxidants are in short supply during aging, it is no surprise that most of the compounds currently being used in anti- aging skin care products have some anti-oxidant properties," explained Dr. Farris. "It's important to realize that just because a product has a logical mechanism of action doesn't mean that it will necessarily erase wrinkles -- there are lots of variables that determine efficacy. The active ingredient must be stabilized, delivered to the skin at a therapeutic concentration and remain in the skin long enough to exert its biochemical effects. Only when these conditions are met can real benefits be seen."
While there are some new agents on the horizon that may give consumers new choices for rejuvenating aging skin, vitamin A -- or retinol -- was the first anti-oxidant to be widely used in cosmetics. There is now a significant amount of scientific evidence that substantiates the benefits of topical vitamin A on aging and sun damaged skin. The synthetic derivatives of vitamin A, called the retinoids, are available by prescription only and have proven even more effective when applied topically.
"The ability of these compounds to soften fine lines and wrinkles, lighten pigmentation, and improve overall photodamage makes them the gold standard against which all new ingredients will be compared," said Dr. Farris.
Alpha Lipoic Acid (ALA)
Alpha Lipoic Acid, or ALA, is a naturally occurring anti-oxidant which is thought to have potent effects. "Most of what we know about ALA is from laboratory data," reported Dr. Farris. What makes ALA unique among anti- oxidants is that it is soluble in both water and lipids. ALA can penetrate skin cells easily through the lipid rich cell membrane and continue to be effective once inside the cell due to its water solubility. ALA has also been shown to exhibit a protective effect on vitamins E and C, thereby boosting natural occurring anti-oxidants within the cell. For these reasons, ALA is now being touted by some as a superior anti-oxidant compound and is incorporated in a number of skin care products.
"Unfortunately, we have very little data on the effects of alpha lipoic acid on human skin," added Dr. Farris. "Preliminary studies suggest that ALA may be beneficial for treating aging skin, but more extensive studies will need to be done before dermatologists can support its use."
First recognized for their ability to enhance wound healing, copper peptides are known to be important in the synthesis of collagen and elastin which makes up the supporting structure of the dermis -- the second layer of the skin. Since the production of both collagen and elastin is reduced in aging skin and skin exposed to ultraviolet light, copper peptides -- in theory -- may be able to help repair photodamaged skin. Accordingly, in the past several years, a number of copper-containing anti-aging skin care products have been marketed.
"Dermatologists have been interested in the effects of copper on skin for many years. Until recently most of the research has been done in the area of wound healing but recent industry-sponsored studies have demonstrated a favorable response to topically-applied copper peptide creams in photodamaged skin," said Dr. Farris.
In double-blind placebo controlled studies, patients using facial creams containing copper peptides showed improvement in fine wrinkling, facial pigmentation and overall photodamage compared to controls. Investigators also noted an increase in skin thickness by an average of 17.8 percent as measured by ultrasound. "Findings like these are encouraging," said Dr. Farris, "but it is important not to oversell these products since in reality they may produce only subtle visible improvements."
"One of the main advantages of copper is that it is non-irritating and relatively inexpensive compared to other anti-oxidant type creams," said Dr. Farris. "For this reason, copper peptide creams may be a good option for patients seeking anti-aging cosmeceuticals but don't want to spend a lot."
Growth factors are a new category of compounds being used to treat aging skin. Extracted from cultured epidermal cells, placental cells, human foreskin and even plants, growth factors are compounds that act as chemical messengers between cells -- turning on and off a variety of cellular activities. Recent studies indicate that a lotion containing kinetin, a plant growth factor, does improve fine lines and wrinkles and can lighten sun- induced pigmentation.
"In this open-label study, all of the participants received the active ingredient. At the end of 24 weeks, fine wrinkles were improved only an average of 13 percent," said Dr. Farris. "While the improvements are not dramatic, there may be a place for this type of product. Kinetin containing lotions are non-irritating and well tolerated, making them a good choice for patients with sensitive skin who can't use products with a propensity to irritate like the retinoids and alpha hydroxy acids."
More recently, human growth factors that are extracted from a variety of tissues are being incorporated into anti-aging cosmeceuticals. These growth factor extracts are like soups and contain a number of active compounds, some of which are important in collagen synthesis.
Histologic studies have confirmed an increase in dermal collagen after topically-applied growth factors. "A multi-center double-blinded clinical study is currently underway to assess the anti-aging effects of human growth factors, and I expect that we'll be hearing a lot about their potential in medical applications in the coming years," said Dr. Farris.
Recently, topical preparations containing dimethylaminoethanol (DMAE) have been touted for their ability to improve skin firmness and lift sagging skin. "This is the first time that we have seen evidence that any topical treatment could be helpful in treating the anatomic changes that occur as a result of aging," said Dr. Farris. Split face studies showed that patients using topical DMAE show subtle yet appreciable lifting of the eyebrows, jowls and cheeks, but the mechanism of action in the skin is unknown.
DMAE has been used as a dietary supplement and is associated with improving mental function and enhancing physical performance -- due in part to its ability to increase the neurotransmitter responsible for stimulating muscles. "We really can't explain the observed effects, but these preliminary studies have raised our interest in the cosmetic benefits of DMAE," added Dr. Farris. Further industry sponsored studies are currently underway.
On the cutting edge are compounds called spin traps. Known for their ability to bind free radicals, spin traps have been used primarily in the laboratory setting in the past but are now being looked at as possible therapeutic agents. Spin traps have anti-oxidant and anti-inflammatory properties, and several companies are now in the development and testing stages with products containing spin trap-like compounds. They have been shown to be beneficial in treating inflammatory conditions like rosacea and sunburn but it remains to be seen if they will be useful as anti-aging agents. "From all indications, I suspect that spin traps will be emerging as a new technology in the war on aging," said Dr. Farris.
While patients looking for the facelift in a bottle probably won't find it in any of the current cosmeceuticals, scientific research in the field of anti-aging continues to give rise to new and promising agents. "It is important to look at the data critically and not to oversell the benefits. As long as patients have a realistic expectation of the kind of improvements they can achieve, cosmeceuticals remain a valuable tool in the treatment of aging skin," said Dr. Farris. "Dermatologists can help patients in selecting the most effective cosmeceuticals. Using topical anti-aging products in combination with other medical and surgical treatments remains the best approach to treating aging skin."
The American Academy of Dermatology, founded in 1938, is the largest, most influential, and most representative of all dermatologic associations. With a membership of over 14,000 dermatologists worldwide, the Academy is committed to: advancing the diagnosis and medical, surgical, and cosmetic treatment of the skin, hair and nails; advocating high standards in clinical practice, education, and research in dermatology; supporting and enhancing patient care for a lifetime of healthier skin. For more information, contact the AAD at 1-888-462-DERM or www.aad.org .
The American Society for Dermatologic Surgery (ASDS) was founded in 1970 to promote excellence in the field of dermatologic surgery and to foster the highest standards of patient care. For more information or referrals to dermatologic surgeons in specific geographic areas, please contact the ASDS Consumer Hotline, 1-800-441-ASDS (2737), during weekday business hours or log on at www.aboutskinsurgery.com .