Background: With age, decreasing dermal levels of proteoglycans, collagen, and elastin lead to the appearance of aged skin. Oxidation, largely driven by environmental factors, plays a central role.
Aim: The aim of this study was to assess the antiaging efficacy of a topical serum containing L-Ascorbic acid, soluble proteoglycans, low molecular weight hyaluronic acid, and a tripeptide in ex vivo and in vivo clinical studies.
Methods: Photoaging and photo-oxidative damage were induced in human skin explants by artificial solar radiation. Markers of oxidative stress - reactive oxygen species (ROS), total glutathione (GSH), and cyclobutane pyrimidine dimers (CPDs) - were measured in serum-treated explants and untreated controls. Chronological aging was simulated using hydrocortisone. In both ex vivo studies, collagen, elastin, and proteoglycans were determined as measures of dermal matrix degradation. In women aged 21-67 years, hydration was measured up to 24 hours after a single application of serum, using Corneometer and hygrometer. Subjects' perceptions of efficacy and acceptability were assessed via questionnaire after once-daily serum application for 4 weeks. Studies were performed under the supervision of a dermatologist.
Results: In the photoaging study, irradiation induced changes in ROS, CPD, GSH, collagen, and elastin levels; these changes were reversed by topical serum application. The serum also protected against hydrocortisone-induced reduction in collagen, elastin, and proteoglycan levels, which were significantly higher in the serum-treated group vs untreated hydrocortisone-control explants. In clinical studies, serum application significantly increased skin moisture for 6 hours. Healthy volunteers perceived the product as efficient in making the skin brighter, more hydrated, and decreasing wrinkles and wished to continue using it. The serum was well tolerated and noncomedogenic.
Conclusion: The serum protected against oxidative damage and dermal protein loss caused by photo- and chronological aging in human skin explants. In-vivo, the serum hydrated skin for 6 hours, and users perceived increased skin brightness, hydration, and fewer wrinkles.
Keywords: L-ascorbic acid; antiaging; antioxidant; proteoglycans; tripeptide; vitamin C.