Development, standardization and validation of in vitro methods for assessing the efficacy of the photoprotective formulation in UVA-I, UVA-II and UVB bands

Abstract

In Brazil, skin cancer is the tumor with the highest incidence and accounts for 25% of all malignant tumors reported in the country. However, the use of sunscreens is increasing proportionally to the incidence of skin disorders associated with ultraviolet (UV) light. This fact may be related to instability filters and excipients of photoprotective formulations, as well as the interactions between them and also the greatest population exposure to the sun due to the high levels of SPF sunscreens. The photoprotective efficacy is only performed at the stage of the product development front to UVB and UVA-II, but not against UVA-I. This study evaluates the FPS that requires the use of human volunteers, professionals, costly equipment and is characterized by complex and time-consuming techniques. For these reasons, the reproducibility of effectiveness during production on an industrial scale becomes impossible. The cosmetic industry has adopted for the quality control of their photoprotective formulations during the production step, methods of high performance liquid chromatography, which quantitate the presence of filters. In this sense, we can see the need for the development, standardization and validation of in vitro techniques less expensive, rapid and reproducible, which provide an analysis of the effectiveness of each batch produced. Therefore, this project is divided into three parts. The first phase of this project has the aim of developing a new method for the in vitro SPF determination of the photoprotective formulations employing cell cultures and spectrophotometric analysis. The second step consists in the development of topical formulations added of Garcinia brasiliensis extract, in evaluating its effectiveness photoprotective and / or fotoquimioprotetora by testing in vivo using hairless mice and in determining your FPS by in vitro method proposed in the first stage of project. This phase is intended to correlate the in vivo results with the results obtained in vitro, in order to attest to the effectiveness and reproducibility of the developed method. The third part aims to develop a novel in vitro method for assessing the efficacy of sunscreens against UVA-I, using cell cultures and mice hairless protected or not by photoprotective formulations via the direct determination of the enzymatic activity of calcineurin and indirectly, by quantification of nuclear factor of activated T cells (NFAT) and the synthesis of interleukin (IL)-2 impacted by UVA-I. It is hoped that this, being able to assess the effectiveness of photoprotective formulations against damage induced by broad spectrum of UV radiation and to ensure the quality of products manufactured every batch completed. (AU)