Beneficial Regulation of Elastase Activity and Expression of Tissue Inhibitors of Matrixmetalloproteinases, Fibrillin, Transforming Growth Factor-β, and Heat Shock Proteins by P. leucotomos in Nonirradiated or Ultraviolet-Radiated Epidermal Keratinocytes

There is loss of the structural integrity of the extracellular matrix (ECM) with intrinsic aging as well as photoaging, largely due to reactive oxygen species (ROS). The structural ECM proteins include the microfibrils that are composed of fibrillin. The structural ECM proteins are primarily degraded by the matrixmetalloproteinases (MMPs) and elastase enzymes. The MMPs are inhibited by the tissue inhibitors of MMPs (TIMPs). A primary regulator of the ECM proteins is transforming growth factor-β (TGF-β), and the chaperone proteins important for its formation are the heat shock proteins (HSP). P. leucotomos extract beneficially regulates of MMPs, TIMPs, and TGF-β in nonirradiated or ultraviolet (UV) radiated fibroblasts and melanoma cells. The hypothesis of this research was that the antioxidant activity or chemistry of P. leucotomos extract would also directly inhibit elastase activity, stimulate the cellular expression of TIMPs, fibrillins, and TGF-β, and regulate HSPs in nonirradiated and UVA or UVB radiated epidermal keratinocytes. P. leucotomos directly inhibited elastase activity, stimulated the cellular expression of TIMPs, fibrillins, and TGF-β, and differentially regulated HSPs in nonirradiated and UVA or UVB radiated epidermal keratinocytes. We infer that the P. leucotomos extract strengthens the ECM and is effective in the prevention or treatment of intrinsic and photoaging of skin.