[Research Notes]

GliSODin® Keeps UV Rays at Bay

PARIS—A vegetarian form of superoxide dismutase (SOD, as GliSODin®, from P.L. Thomas) demonstrated significant reduction in oxidative stress (sun burn) in a model using ultraviolet (UV) radiationinduced skin changes. Phototypes II endured a longer light exposure to create the skin burn after supplementation, compared to placebo. In the double blind, placebo-controlled study, UV skin burn (actinic erythema) was induced on the inner-forearms of 49 healthy subjects before supplementation with GliSODin (www.glisodin.org) or placebo, and then once weekly over a four-week period with daily supplementation. The color of the skin was measured by chromometry; inflammation was assessed by videocapillaroscopy (which calculates the congestion of small blood vessels). The redness caused by the UV skin burn decreased more quickly in the GliSODin group. Regeneration of capillaries in the skin—a measure of recovery and reduction of inflammation—was higher in the GliSODin group compared to placebo. The study, published April 2007 in the European Journal of Dermatology (17, 2), was conducted by researchers at the Cutanees Engineering and Research Laboratory, Besancon, France.

ROME—Xanthophyllic carotenoids administered orally and topically had synergistic effects in protecting the skin from ultraviolet (UV) radiation (Skin Pharmacol Physiol, 20, 4:199-210, 2007). In a double blind, placebo-controlled trial at St. Eugenio Hospital, Rome, researchers examined the efficacy of lutein and zeaxanthin on five skin physiology parameters—surface lipids, hydration, photoprotective activity, skin elasticity and skin lipid peroxidation—in human subjects. Carotenoids were administered orally, topically or in combination of oral and topical routes. At study’s end, researchers found the combination of oral and topical administration provided the greatest degree of antioxidant protection, although both also provided significant activity in the skin when administered through a single route. Oral administration of lutein was found to be more protective than topical application when measured by changes in lipid peroxidation and photoprotective activity in the skin following UV light irradiation.

FORT LAUDERDALE, FLA.—Tomato lycopene complex (as Lyc-O-Mato®, LycoRed) was found to have sun protective properties, helping to prevent premature aging of the skin. Presented by Yossi Levy, Ph.D., professor of clinical biochemistry at Ben Gurion University, Beer Sheva, Israel, at the Cosmeceutical Summit in Fort Lauderdale, Fla., two studies show oral consumption of carotenoids (lycopene, phytoene, phytofluene) from tomato helps maintain healthy skin by protecting it against UV-induced damage. The first study, conducted at the University of Düsseldorf, Germany, examined the photo-protective effects of both natural Lyc-O-Mato and synthetic lycopene. Both affected a decrease in the reddening of the skin of the participants, indicating protection from UV-induced damage; however, the group that ingested synthetic lycopene showed only a 25 percent reduction in redness, whereas Lyc-O-Mato afforded superior protection with a 38 percent reduction. The second study, conducted at the Universities of Witten/Herdecke and Düsseldorf, Germany, involved three groups of participants. Two different antioxidant supplements containing carotenoids and selenium were tested for their impact on skin structure and health. Groups one and two received different levels of a mixture of lycopene, lutein, beta-carotene, alpha-tocopherol and selenium; group three (control) received placebo. After 12 weeks, participants in the intervention groups showed a significant increase in skin density and thickness, improvement in skin smoothness and softness and reduced scaling; there was no improvement in the placebo group.

ANKARA, TURKEY—Epigallocatechin-3-gallate (EGCG) may prevent ultraviolet (UV) A-induced skin damage when applied prior to exposure (J Eur Acad Dermatol Venereol, 21, 5:650-6, 2007). Researchers from Ankara Numune Education and Research Hospital divided 24 12-week-old albino rats into four groups (n=6): Group I, control; Group II, UVA exposure; Group III, topical EGCG (hydrophilic ointment, 2-percent EGCG) 30 minutes after UVA exposure; Group IV, topical EGCG 30 minutes prior to UVA exposure. Group IV had a statistically significant decrease in sunburn cells and dermo-epidermal activation compared with Group II. No difference was detected between groups II and III, suggesting EGCG must be applied topically prior to UVA exposure to protect against skin damage.

MUMBAI, INDIA—Using a solid lipid nanoparticle (SLN) carrier system for topical application of vitamin A palmitate increased bioavailability of the compound and improved skin hydration (AAPS PharmSciTech, 7, 4:91, 2006). Researchers from SNDT Women’s University prepared topical gels enriched with vitamin A SLN using polymeric gels of carbopol, pemulen, lutrol and xanthan gum. In vitro release profile from the nanoparticular dispersion showed prolonged release up to 24 hours, which researchers attributed to embedment of the compound in the solid lipid core. In vitro penetration studies showed the SLN system doubled the vitamin A palmitate concentration in the skin, compared with conventional gel. Also, in vivo skin hydration studies in albino rats showed an increase in the thickness of the stratum corneum with improved skin hydration, with no irritation.

BIRMINGHAM, ALA.—Polyphenols found in green tea (Camellia sinensis), particularly epigallocatechin- 3-gallate (EGCG), may help protect the skin from UV carcinogenesis (J Nutr Biochem, 18, 5:287-96, 2007). In a review article from the University of Alabama at Birmingham, researchers examined recent studies that have defined the photoprotective activity of green tea polyphenols (GTPs). Oral or topical administration of GTPs or EGCG may prevent UV-induced skin tumor development by inducing immunoregulatory cytokine interleukin (IL) 12; aiding IL-12 dependent DNA repair; inhibiting UVinduced immunosuppression; inhibiting angiogenic factors; and stimulating cytotoxic T cells in a tumor microenvironment.

QUEBEC—DMAE (2-dimethylaminoethanol) induces vacuolar cytopathology, expanding and strengthening cell walls, which may account for its efficacy as a topical antiwrinkle agent. Researchers from the Univeritaire de Quebec conducted in vitro tests with cultured rabbit dermal fibroblasts treated with tertiary amines, and with primary cultures of human cutaneous epithelial cells. Further in vivo research used the inner skin of the rabbit ear for morphological verification of the vacuolization caused by topical DMAE. Both the fibroblasts and human epithelial cells responded to DMAE by massive vacuolization; adding the vacuolar adenosine triphosphatase inhibitor bafilomycin A1 slowly reversed the effects. In addition, the epidermis of the rabbit ear was significantly thickened and exhibited perinuclear swelling indicative of vacuolization in response to 3-percent DMAE. The study appeared in the British Journal of Dermatology (156, 3:433-9, 2007).

KANGWON, KOREA—A polysaccharide extract from Ulmus davidiana var. japonica (Japanese elm) has potential as a cosmeceutical ingredient, according to Korean researchers (J Cosmet Sci., 57, 5:355- 67, 2006). HPLC experiments showed the composition of the extract was primarily rhamnose, galactose and glucose, with a molecular weight of 20,000 and intrinsic viscosity of 90 dl/g. In a moisturizing test, Ulmus davidiana extract showed similar effects as hyaluronic acid (HA). The extract also had the ability to inhibit H(2)O(2)-activated release of inflammatory PGE2 and IL-6 in a dose-dependent manner; IL-8 release was completely inhibited. Finally, in a test of recovery from ultraviolet (UV) A-induced skin damage, cell recovery of human fibroblast cells was twice as high in the group treated with Ulmus davidiana extract.