Background: Exposure to ultraviolet (UV) radiation induces generation of reactive oxygen species, production of proinflammatory cytokines and melanocyte-stimulating hormone (MSH) as well as increase in tyrosinase activity. The potential photoprotective effects of Coccoloba uvifera extract (CUE) were evaluated in UV-stimulated melanocytes.
Methods: Human epidermal melanocytes were used as an in vitro model to evaluate the effects of CUE on the production interleukin-1alpha (IL-1alpha), tumor necrosis factor alpha (TNF-alpha), and alpha-MSH under basal and UV-stimulated conditions. Antioxidant and anti-tyrosinase activities were also evaluated in membrane lipid peroxidation and mushroom tyrosinase assay, respectively.
Results: Coccoloba uvifera L. showed antioxidant and anti-tyrosinase activities and also inhibited the production of IL-1alpha, TNF-alpha and alpha-MSH in melanocytes subjected to UV radiation (P<0.01). Moreover, CUE inhibited the activity of tyrosine kinase in cell culture under basal and UV radiation conditions (P<0.001), corroborating the findings of the mushroom tyrosinase assay.
Conclusion: This study supports the photoprotective potential of CUE.