Suntan Accelerator is a preparation rich in tyrosine and riboflavin that stimulates the biochemical reactions of melanin formation in the skin.

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1 Suntan Accelerator INTRODUCTION Suntan Accelerator is a preparation rich in tyrosine and riboflavin that stimulates the biochemical reactions of melanin formation in the skin. Melanin is a dark pigment which is synthesized in the melanocytes located at the lower layer of the epidermis. This pigment acts as a natural filter of the sun ultraviolet radiation. The formation of melanin is the consequence of the melanocyte reaction against an UV radiation. The quantity of melanin produced, depends on the duration, intensity and frequency of the exposition under ultraviolet light. The biochemical process of the melanin formation is quite complex: the tyrosine amino acid, present in the melanocytes, is oxidised by means of certain redox activators (tyrosinases, riboflavin) and also by the presence of light, oxygen and heat to 3,4-dihydroxyphenylalanine (DOPA). DOPA is also oxidised to dopaquinone and by means of a later oxidation and polymerization, melanin is formed. Melanin has two different varieties: eumelanin, with a dark brown-blackish colour and pheomelanin, with a brownyellowish colour. The first one existing especially in black and brown dark skin people, and the second one in blond or red-haired people. Figure 1. Melanin synthesis pathway. V 03-05/10

2 From the physiologic point of view, the formation of melanin is produced as follows: first of all, tyrosinase is produced at the melanocytes ribosomes; then it passes through the endoplasmic reticulum to the Golgi apparatus, where it is accumulated as small vesicles. Then starts the melanosome formation (very rich in tyrosine), where the tyrosine accumulated in the Golgi apparatus is transferred. Here is where the consecutive biooxidations that lead to the melanin formation take place. By means of vermiform elongations originated in the melanocytes, the melanin synthesized at the melanosomes passes to the keratinocytes, colouring them. The pigment formed by the melanocytes of the lower layer is transferred to the keratinocytes of the epidermis deepest layers, which migrates to the most external layers. This process results in a more or less tanned colour, which at the same time acts as a protection against the UV solar radiation. The skin of white people is poorly pigmented. When it is exposed to the direct action of sun light, UV radiation promotes a great stimulation of melanocytes, with the corresponding melanin increment. However, melanin needs some days to arrive to the most superficial layers of the skin. For these reasons, the pigmentation appears after some days and as in the meantime there is not enough protection some troubles such as redness, irritation and skin burning in the most serious cases appear. To avoid this problem, it is necessary to use preparations including synthetic sun filters, which will replace the initial lack of melanin. On the other side, with a high protection the skin will be tanned very slowly and in some cases very lightly. By adding a preparation which accelerates the formation of melanin in the suntan products with a sun filter, we will obtain a quicker suntan without leaving the skin unprotected. This is the basic principle of the Suntan Accelerator, which will satisfy the essential requirements of solar baths: to obtain the maximum coloration in the minimum time, by causing the minimum damage possible to the skin. CHEMISTRY Suntan Accelerator is presented as a solution which includes the following active components: Tyrosine Riboflavin (Vitamin B) COSMETIC PROPERTIES The formation of melanin in the skin needs the amino acid tyrosine but it also requires the co-operation of light, heat, oxygen and tyrosinase (enzyme). This last enzyme is an oxidase that makes possible the first step of the tyrosine oxidation, helping the final pigment formation. It has been experimentally proved that the single addition of tyrosine in a preparation does not give perceptible results in the skin, since it is necessary the presence of a catalyst of tyrosine oxidation to DOPA. Such oxidation takes place in the skin by means of tyrosinases, but due to its inestability, it is not possible to include it in suntan accelerator preparations. Therefore, instead of tyrosinase the use of riboflavin is more useful, as it also catalyses the tyrosine oxidation process. V 03-05/ ,

3 COSMETIC APPLICATIONS It intensifies the formation of skin melanin. For this reasons, by adding it to the suntan preparation, it helps getting a quicker, intense and lasting tanning. It is important to consider that Suntan Accelerator does not have any sun protecting effect, so it has to be accompanied by a proper sun filter. It helps to obtain a quicker, more intense and long lasting suntan, with the minimum skin damages. EFFICACY TEST 1 Target of the study An study was realized to quantify the level of suntan acquired in the skin after a treatment with a cosmetic product containing only Suntan Accelerator at a concentration of 3.5% (B), Suntan Accelerator plus sun filter (C) or just the cosmetic base (A). The final target was to confirm the effectiveness of the Suntan Accelerator as a suntan activator. Experimental method In this study 15 women were chosen, between 23 and 44 years old, and with a phenotype III or IV (Mediterranean average skin). Three equal zones with a similar skin tone were delimitated in the forearms of the volunteers. Each of the three products (A, B or C) was applied in the corresponding zone for 15 days at the same time of the day, being uniformly extended until it was completely absorbed. Afterwards, the zones were irradiated following the methodology of the Schulze study. Measurements of suntan levels of the volunteers were realized using the Elrephomat model of Zeiss colorimeter. At the beginning of the study the color of these three selected areas was analyzed in all volunteers. Measurements taken during and after the test determined the changes of color produced in each zone compared with the initial values. Results From all of the above, it is possible to deduce the following conclusions: The cream which contained the Suntan Accelerator (B) produced a more intense tan at a faster rate than the cream which did not contain the product (A). The cream which contained the Suntan Accelerator in addition to a solar filter (C) produced a less intense tan at a slower rate than the cream which did not contain the product (A). The differences among the values obtained from the three creams after the application-exposure period were statistically significant. EFFICACY TEST 2 Aim of the study The final aim of the study was to confirm the in vivo effects of the Suntan Accelerator in the skin (compared with a placebo product and a control zone) when applied before receiving solar radiation. Experimental method Ten volunteers were selected from 10 to 60 years old, belonging to the phenotype III or IV according to Fitzpatrick s classification. Three zones of 100 cm 2 were delimitated in their backs to apply the cosmetic product with Suntan Accelerator (at a concentration of 2%), placebo (product without active ingredient) or nothing (control zone). V 03-05/ ,

4 In the treated zones, products were applied once a day during 15 consecutive days (except weekends) and 2 hours before the sun exposure at maximum. The control zone had no product application. Sun exposures took from 6-8 minutes and were received by the volunteers during two weeks except weekends. After obtaining the melanin values using the relation between the absorbed and reflected light by the skin, the curve slopes and suntan increases were calculated for the three zones and compared among them. Results Results of the melanin content are shown in the graphics below. The enhancing effect of the Suntan Accelerator related to the other curves can be clearly seen. The suntan accelerating effect was observed in 90% of volunteers. The small decrease in day 8 and 15 was due to the non exposure of the volunteers during weekends. Melanin index Days Comparing the different treatment groups and realizing a statistical test, it can be said that the skin treated with Suntan Accelerator gets 2.9 times more suntanned than the control zone and also versus a non significant increase of 1.3 obtained by the placebo group. Moreover, the slopes of the zone treated with the active are clearly more pronounced than the other two zones, showing that it also increases the suntan speed of the skin in an important manner. Conclusion Considering the results of the two efficacy tests realized, Suntan Accelerator generates a clear and relevant increase of the suntan induction, causing a melanin augment of 2.9 times versus the non treated zone. Suntan accelerator increases suntan speed and intensity in a clear and visible way. RECOMMENDED DOSE The recommended dose is between 2.0% and 3.5%. V 03-05/ ,

5 BIBLIOGRAPHY Février, F., Bobin, M.F., Lafforgue, C., Martín, M.C. Advances in microemulsions and transepidermal penetration of tyrosine. STP Pharm Sci 1:60, 1991; 1(1): (ref.716). Fitzpatrick, T.B., Szabó, G., Wick, M.M. Biochemistry and Physiology of melanin pigmentation. In: Goldsmith LA (ed.). Physiology, Biochemistry and Molecular Physiology of the Skin. Oxford University Press, New York, pp , 1983 (ref. 2308). Guglielmini, G. Substantiating claims for a tanning magnifier. C&T, 2004; 119(6): (ref.6651). Meredith, P., Sarna, T. The physical and chemical properties of eumelanin. Pigment Cell Res., 2006; 19(6): (ref. 8839). Prota, G. Melanins and Melanogenesis. C&T 1996; 111: (ref. 1585). Riva, A., Prieto, M. Acelerador del bronceado. Determinación de la Eficacia por Colorimetria. Industria farmaceutica, 1989; 4 (6): (ref. 4262). Riley, P.A. The mechanism of skin pigmentation production. J. Soc. Cosmet. Chem. 1977; 28: (ref. 2303). Sánchez-Ferrer, A., Rodríguez-López, J.N, García-Canovas, F., García-Carmona, F. Tyrosinase: a comprehensive review of its mechanism. Biochim Biophys Acta. 1995; 1247(1):1-11 (ref. 4174). Stanzi, K., Thiry, D., Röding, J., Zastrow, L. Development and Testing of a New Suntan Accelerator. SÖFW-Journal, 1992; 118: (ref.717). V 03-05/ ,