Background: Ultraviolet (UV) irradiation triggers skin photoaging processes, which disrupt the normal three-dimensional integrity of skin. UV-induced oxidative stress, both directly and indirectly, stimulates complex signaling pathways. UV radiation activates skin cell surface receptors on a molecular level and triggers severe changes in extracellular matrix (ECM) proteins, resulting in skin photoaging.
Aims: Sclareol isolated from Salvia officinalis is widely used as a fragrance material. Sclareol is known to exert various biological activities, but its antiphotoaging effect has not been elucidated to date. Therefore, we evaluated wrinkle improvement efficacy of sclareol.
Methods: Human dermal fibroblast cell line (Hs68) and a reconstructed human epidermis (RHE) model were used to evaluate the antiphotoaging effect of sclareol in vitro. A clinical study treated with 0.02% sclareol-containing cream was conducted to identify the ability of sclareol to improve wrinkles.
Results: First, sclareol enhanced cellular proliferation and blocked UVB-induced cell death. Sclareol inhibited the UVB-induced mRNA expression of matrix metalloproteinases (MMPs) by regulating the protein expression of AP-1 constituents. In RHE model, sclareol recovered the UVB-induced decrease in epidermal thickness and the expression of proliferating cell nuclear antigen (PCNA). In clinical trial, visually assessed changes and several wrinkle parameters were considered to be statistically different between the test and control groups at 12 weeks.
Conclusions: In this study, sclareol inhibited various photoaging phenomena in human fibroblasts and RHE model. In addition, sclareol-containing cream improved wrinkles in a clinical trial. Taken together, sclareol alleviates facial wrinkle formation via an antiphotoaging mechanism and may be an effective candidate ingredient.
Keywords: facial lines; fibroblast; photoaging; sclareol; skin equivalent.
© 2016 Wiley Periodicals, Inc.