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Aesthetic Dermatology Cosmeceuticals
Innovations in Treating Photodamaged Skin
May J Chow
1
and Dominique Boineau-Géniaux
2
1. Director, Dermatology, WellGroup HealthPartners, Chicago Heights; 2. Dermatologist, Aesthetics, Bordeaux
Abstract
Together with living in a polluted, oxygen-rich environment, ultraviolet A (UVA) and B (UVB) radiation from the sun cause premature
photoageing and may induce pre-cancerous changes such as actinic keratoses (AK). Reactive oxygen species (ROS) are an innate part of
the build-up and break-down process of the skin. It has been well established that the use of sunscreens prevents the penetration of
harmful UV rays into the skin. However, studies have shown that even the best sunscreen protects against only 45–55% of free radicals
generated by routine sun exposure. In contrast to sunscreens, topical antioxidants are absorbed into the skin and cannot be rubbed or
washed off, providing significant protection against acute UV injury and neutralising ROS before they can damage the skin. These facts
further support the importance of using a topical antioxidant once daily to cover the remaining 45–55% of daily environmental damage that
sunscreen cannot prevent. Particular attention has been given to topical antioxidant serums containing vitamin C and E stabilised by ferulic
acid, a highly potent formulation that can penetrate the skin. This combination offers photoprotective benefits, including the reduction of
erythema, sunburn cell formation, carcinogenic DNA changes, UV immunosuppression and, subsequently, AK, skin cancer and
photoageing. The addition of phloretin to antioxidant formulations can inhibit tyrosinase and reduce hyperpigmentation. Medical skin
expertise, with its preventative strategies and methods of treatment, is in demand from patients who are now much better informed and
seek a global approach. This observation has inspired Dominique Boineau-Géniaux and her team to develop a unique concept,
unprecedented in France: a centre of cosmetic dermato-surgery and nutritional medicine known as Aesthetics, located in Bordeaux.
Keywords
Topical antioxidants, cosmeceuticals, photoprotection/photoageing, actinic keratosis, sunburn cell, hyperpigmentation, tyrosinase, skin cancer,
pure vitamin C, phloretin, reactive oxygen species (ROS), free radical scavenger, aesthetic centre, non-invasive procedures
Disclosure: The authors have no conflicts of interest to declare.
Received: 11 March 2009 Accepted: 23 April 2009
Correspondence: May J Chow, WellGroup HealthPartners, 333 Dixie Hwy, Chicago Heights, IL 60411, US; Dominique Boineau-Géniaux, Dermatologist, Aesthetics, 4 avenue
Carnot, 33200 Bordeaux, France.
Combination of Standard Medical Therapies, practice we are attempting to decrease the recurrence of AK post-
Topical Antioxidants and Sunscreen treatment as well as to prevent the development of skin cancer.
by May J Chow Clinically, we have observed that sunscreen, sun-protective clothing
Actinic keratosis (AK) is one of the most common skin conditions and avoiding the sun are still inadequate for preventing the
seen in my practice (see Figures 1 and 2). Overall, the rate in the US recurrence of AK. In this article, we discuss available topical
is estimated to range from 11 to 26%,
1
and in Australia from 40 to antioxidants and how they can work synergistically with sunscreen
60%.
1
More importantly, the incidence of skin cancer in the US is as a means of maintaining healthy skin after medical treatment.
more than 1 million annually compared with 1.4 million for all other
cancers combined.
2
AK are pre-malignant lesions formed by chronic Sunlight consists of ultraviolet A (UVA) and B (UVB) rays, which are
sun exposure and DNA damage in the cells, specifically in the both harmful. UVA rays can pass through glass and can penetrate
epidermis. One to 10% of all AK have the malignant potential to deeply into the dermis. Additionally, UVA can suppress the immune
become squamous cell carcinoma (SCC) (see Figure 3). The system and therefore the body’s innate ability to protect against the
formation of AK is a long process, often taking many years to development and spread of skin cancers. UVB rays (blocked by
develop; therefore, many patients do not realise that sun damage glass) are the main cause of sunburn. Excessive exposure to UV
acquired during childhood has the potential to become AK and rays, for instance in the use of tanning beds or daily participation in
subsequently SCC in late adult life. outdoor activities, can lead to an acute inflammatory response.
These reactions include sunburn as well as chronic actinic damage
Many evidence-based medical modalities are currently used to treat similar to radiation dermatitis.
AK, including liquid nitrogen cryotherapy, topical 5-fluorouracil,
topical imiquimod and photodynamic therapy utilising 5- UVA and UVB radiation from the sun, together with living in a
aminolevulinic acid as a photosensitiser and a light source. In our polluted, oxygen-rich environment, causes premature photoageing,
© TOUCH BRIEFINGS 2009 49
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