Roles of matrix metalloproteinase and tissue inhibitors of metalloproteinases in photoaging

Ultraviolet (UV) irradiation has harmful effects on human skin,Photoaging is currently considered as a primary harmful effect of chronic solar UV exposure.UV irradiation can induce increased expression of certain members of the matrix metalloproteinase (MMP) family,which in turn degrade dermal collagen and other extracellular matrix (ECM) proteins,then lead to the disruption of normal architecture of skin connective tissue followed by the impairment of skin function and aging of skin.Tissue inhibitors of metalloproteinases (TIMPs) are considered as the specific endogenous inhibitor of matrix metalloproteinases (MMPs),and participate in the regulation of MMP activity.The balance between MMPs and TIMPs plays an important role in the occurrence and development of skin aging. Key words: Photoaging ;  Matrix metalloproteinase ;  Tissue inhibitors of metalloproteinases ;