INHIBITION OF UV INDUCED MMP-1 IN EPIDERMAL EQUIVALENTS BY ANTIOXIDANTS.

Chronic exposure to sunlight has been shown to induce matrix metalloproteinase (MMP) synthesis in human skin, resulting in elevated levels of MMPs and contributing towards photoagng. Reactive oxygen species (ROS) are believed to be important second messengers in this process resulting in an up-regulation of c-fos and c-jun which bind to form the transcription factor AP-1. Using human epidermal equivalents, we demonstrate in vitro an up-regulation of MMP-1 mRNA and secreted protein following irradiation with solar spectrum light. We also demon-strate that antioxidants such as ascorbic acid, α-tocopherol or green tea polyphenols are able to provide dose-related protection against this UV induced MMP synthesis. Using this model we are able to screen for natural antioxidants and synergistic cocktails of actives that may be useful to protect against UV induced matrix degradation and photoagng.

Ascorbic acid, EpiDerm, Green tea, MMP, Matrix metalloproteinase, Messenger RNA (mRNA), ROS, Reactive oxygen, Reactive oxygen species, Tocopherol