Rubus idaeus L. (red raspberry) blocks UVB-induced MMP production and promotes type I procollagen synthesis via inhibition of MAPK/AP-1, NF-κβ and stimulation of TGF-β/Smad, Nrf2 in normal human dermal fibroblasts

Chronic exposure to UV radiation results in skin premature aging (photoaging), clinically accompanied with loss of elasticity and tension. In this study, we demonstrated that RI could reverse this damage via increasing procollagen synthesis and blocking MMPs, inflammatory factors expression. The studies of molecular mechanism indicated RI could inhibit MMPs expression via inactivating MAPK/AP-1, NF-κβ pathway and accelerate type I procollagen synthesis through activating the TGF-β/Smad pathway. Furthermore, RI reduced UVB-enhanced ROS via promoting Nrf2 nuclear location and enhancing the expression of cytoprotective antioxidants.111