238 Retinol at a concentration of 0.3% restores fibrillin-rich microfibrils and modifies the epidermis in photoaged human skin in vivo in a manner similar to 1% retinol

Abstract

Whilst retinol concentrations of 1% weight/volume (w/v) in skincare cosmetics are commonplace within the US market, lower percentage formulations are associated with fewer tolerance issues. Here we investigated the effect of retinol at 0.1%, 0.3% and 1% w/v upon epidermal barrier, keratinocyte proliferation and deposition of fibrillin-rich microfibrils (FRM) in a 12-day in vivo patch test. The vehicle control (VC) and retinol formulations were applied under occlusion to photoaged forearms of healthy volunteers (n=5; 66-84 years) prior to biopsy and analysis of key biomarkers of skin health.