Efeitos do extrato de Lycium barbarum L. e do laser vermelho na prevenção e tratamento do fotoenvelhecimento cutâneo em camundongos hairless

Abstract

In the aging process an organic functional decrease occurs. Ultraviolet Radiation (UVR), from the sun, is its main etiological agent. Cellular and structural changes arise as a consequence of the association between UVR and chronological aging. Experimental research on aging should be developed from parameters that separate the characteristics of photoaging from chronological aging and the search for animal models with a tegument structure analogous to that of humans. Different strategies are used for the prevention and treatment of photoaging. The phytochemical analysis of many plants used for this purpose has been shown to contain substances that have important antioxidant effects in the prevention and treatment of photoaging. Photobiomodulation (PBM) is widely indicated in the treatment of photoaging and has been used in different intensities to stimulate or inhibit cellular processes and to facilitate the absorption of substances used as protectors against cell damage. The molecular effects of cellular photobiomodulation therapy have not yet been fully demonstrated and there is a need for further studies that elucidate these mechanisms and understand the beneficial effects of this therapy, including the photoaging process. Thus, the purpose of this study is to investigate and contribute to the elucidation of the isolated and associated action of red laser and Lycium barbarum fruit extract in the prevention and treatment of induced photoaging in the dorsal skin of hairless mice, by identifying the main components of a polysaccharide fraction isolated from the extract of the fruit of Lycium barbarum (LBP fraction) by nuclear magnetic resonance and the techniques of histology, immunohistochemistry and immunofluorescence for qualitative and quantitative analysis of skin components. The results revealed that the bioactive molecules of the LBP fraction have antioxidant and permeation potential in the skin. The treatments performed with the LBP fraction and photobiomodulation during photoaging induction were effective in protecting the skin from epidermal thickening in all experimental groups and degradation of collagen fibers, except for the group that was first treated with LBP fraction and then with the red laser. The treatments were not able to reduce the levels of MMPs in the skin of hairless mice induced by UVR. On the other hand, treatments performed after UVR-induced photodamage decreased epidermal thickening, c-Fos and c-Jun (AP-1) levels and MMP-1, 2 and 9 expression levels on the dorsal skin of the hairless mice of all experimental groups. The group that was treated first with the photobiomodulation and then with the LBP fraction showed an increase of the levels of collagen I, III and FGF2, suggesting a synergism in this order of application. The results suggest the possible use of the LBP fraction in cosmetic formulations due to its antioxidant and permeation potential and its use in association with red laser for the purpose of skin photorejuvenation treatment in aesthetic procedures.