Torloni LBO, Vanzo-Jr AC, Pereira AFC, Lage R, Mercuri M, Silva SG, Satake CY, Maciente GO, Pereira AF, Silva MS, Facchini G, Pinheiro ALTA, Eberlin S.
Keratinocytes, suffer numerous biochemical reactions during the transition from basal layer to stratum corneum (SC), including synthesis of specific basal (K14) and suprabasal (K10) keratins and cornified envelope-associated proteins. Epidermal differentiation complex (EDC) is constituted through cross-linking of involucrin, loricrin, profilaggrin, among others, on intracellular surface of plasma membrane in upper spinous and granular layers of epidermis1-3. Studies has shown many factors, such skin inflammatory process and prolonged exposure to sunlight, could affect the skin barrier and extracellular matrix inducing a decrease in the synthesis of the major dermal proteins, collagen and elastin, clinically characterized by wrinkles, rough skin and loss of water and skin tone4. In this study, we evaluated the effects of a cosmetic formulation on the production of aquaporin-3, envelope proteins filaggrin, involucrin, keratin 10 and 14, and extracellular matrix collagen type I and III using an in vitro and ex vivo model of human skin. Human fibroblasts and keratinocytes were incubated with the cosmetic formulation (GLYd) for further quantification of aquaporin-3, filaggrin, involucrin, keratin 10, keratin 14, collagen type I and III. Human fibroblasts were additionally subjected to oxidative stress by UV radiation to mimic skin aging. Cell supernatants and lysates were collected and mediators were quantified using colorimetric sandwich assay (ELISA). Fragments of human skin, from elective plastic surgery, were treated with GLYd and forwarded to immunohistochemistry evaluation for involucrin, keratin 10 and keratin 14. Anova followed by the Bonferroni test was used to compare data among all groups. Our results demonstrated that incubation of keratinocytes cultures with GLYd increased levels of aquaporin-3, filaggrin, involucrin, keratin 10 and keratin 14, reaching-up to 2.80, 1.92, 2.20, 2.16 and 2.14-fold increase, respectively, in relation to non-treated control. The effects of GLYd were also confirmed by the immunohistochemical evaluation of involucrin, keratin 10 and keratin 14 in human skin culture. GLYd treatment was able to protect fibroblast cultures against significant reduction in the synthesis of collagens type I and type III, induced by UV radiation. The results obtained allow us to infer that GLYd exerts an effect on the skin hydration and renewal by increasing the production of aquaporin 3, involucrin, filaggrin, keratins 10 and 1, besides playing a role in the skin protection, preventing the reduction of type I and type III collagen production induced by exposure to UV radiation.