Introduction: The skin may present dysfunctions that result in histological alterations and elementary lesions, many of them caused by immunologic mechanisms and/or alterations in the epidermal barrier. Objective: The present study was aimed at verifying in vitro whether some cosmetic products marketed in Brazil in the form of liquid soaps, have anti-inflammatory and protective efficacy in the skin barrier. Methods: An in vitro study was carried out with four commercial soaps, which were evaluated in a cell culture of human keratinocytes for the determination of their anti-inflammatory and epidermal barrier restorative effects, as well as their capacity to reduce cutaneous hypersensitivity. Concentrations of keratin 10 and 14, loricrin, IL-12, IFN-γ and TRP V-1 were measured in the cell culture supernatants of human keratinocyte through the sandwich ELISA assay. Results: The four test substances led to significant reductions in the synthesis of IFN-γ and IL-12. Only the test substance C triggered a significant increase in the synthesis of keratin 10. All test substances showed significant reductions in the synthesis of keratin 14 and TRPV-1, and a significant increase in the synthesis of loricrin. Conclusions: Some cosmetic products in the form of soap can have in vitro results regarding their anti-inflammatory, epidermal barrier restoration and skin hypersensitivity reduction effects.

Keywords: ANTI-INFLAMMATORY AGENTS/ADVERSE EFFECTS; DERMATITIS, ATOPIC; SOAPS

Introdução: Hyperpigmentation is a common dermatological condition, usually associated with exposure to the sun and relative difficulty of treatment. Pycnogenol^® is an extract obtained from the French pine tree Pinus pinaster, with known antioxidant and anti-inflammatory activity, having been proven to inhibit melanin synthesis in previous studies. Objective: To evaluate the whitening activity of Pycnogenol^® in an ex vivo experimental model after exposure to ultraviolet A and B, infrared-A radiations and visible light. Method: Human skin fragments obtained from elective plastic surgery were treated with Pycnogenol ^® and then irradiated with ultraviolet A and B, and infrared-A radiations, and visible light, having been sent for histological evaluation of melanin pigmentation by the Fontana-Masson staining technique. Results: The histological evaluation demonstrated an increase in melanin deposition in all irradiated groups. However, fragments pre-incubated with Pycnogenol^® showed a reduction in the deposition of this pigment after irradiation. Conclusions: This study demonstrates the reduced melanin deposition in skin culture treated with Pycnogenol^® after irradiation with ultraviolet A and B, and infrared-A radiations, and visible light, concluding that this substance may have lightening properties.

Keywords: HYPERPIGMENTATION; SKIN LIGHTENING PREPARATIONS; SOLAR RADIATION