ABSTRACT
Chronic exposure to ultraviolet (UV) radiation causes photo-oxidation, which in turn results in the upregulation of matrix metalloproteinases (MMPs) and loss of collagen. Rubus idaeus L. (RI), also called red raspberry, is an important cash crop that contains abundant antioxidant compounds. Sanguiin H-6 and lambertianin C are the major ingredients presented in the extracts. Here, we studied the protective effect of RI on UVB-induced photoaging in normal human dermal fibroblasts (NHDFs). We found that RI notably reduced UVB-induced MMPs secretion and pro-inflammatory mediators production, and significantly suppressed UVB-induced activation of mitogen-activated protein kinase (MAPK), nuclear factor-κß, as well as activator protein 1. Additionally, treatment of NHDFs with the ERK inhibitor (PD98059) and JNK inhibitor (SP600125) resulted in the reduction of UVB-induced MMP-1 and IL-6 expressions, which demonstrated that the inhibition of MMP-1 and IL-6 by RI is associated with the MAPK pathway. Furthermore, we also found that RI accelerated procollagen type I synthesis by activating the transforming growth factor-ß/Smad pathway and enhanced the expression of cytoprotective antioxidants such as heme oxygenase-1 and NHD(P)H quinone oxidoreductase 1 by promoting nuclear factor E2-related factor 2 nuclear transfer. Overall, these findings demonstrated that RI was potentially effective in preventing UVB induced skin photoaging.
Subject(s)
Collagen Type I/metabolism , Matrix Metalloproteinases/metabolism , Plant Extracts/pharmacology , Rubus/chemistry , Signal Transduction/drug effects , Ultraviolet Rays , Antioxidants/chemistry , Antioxidants/metabolism , Cell Line , Cell Survival/drug effects , Cell Survival/radiation effects , Dermis/cytology , Fibroblasts/cytology , Fibroblasts/drug effects , Fibroblasts/metabolism , Humans , Interleukin-6/metabolism , Mitogen-Activated Protein Kinases/metabolism , NF-E2-Related Factor 2/metabolism , NF-kappa B/metabolism , Phenols/chemistry , Phenols/isolation & purification , Phenols/pharmacology , Plant Extracts/chemistry , Rubus/metabolism , Signal Transduction/radiation effects , Smad Proteins/metabolism , Transcription Factor AP-1/metabolism , Transforming Growth Factor beta/metabolismABSTRACT
UV radiation is the primary cause of skin photoaging, which results in an increase in matrix metalloproteinases and degradation of collagen. Developing new natural antioxidant as photoprotective agents has become a popular area of research. Orobanche cernua Loefling is a parasitic plant that is rich in phenylethanoid glycosides (PhGs). This study investigated the photoprotective effects of the ethanolic extract of Orobanche cernua Loefling (OC) and its principal component acteoside on UVB-induced photoaging as well as their underlying molecular mechanisms in normal human dermal fibroblasts (NHDFs). Biological testing demonstrated that OC and acteoside possessed significant photoprotective activities, reducing MMP and IL-6 levels while improving type-I procollagen synthesis in UVB-irradiated NHDFs. Further study showed that the protective mechanisms were the improvement of transcription factor Nrf2-mediated antioxidant defensive system, suppression of MAPK/AP-1 and activation of the TGF-ß/Smad pathway. Together, our results suggested that OC might be a promising antiphotoaging agent against UV radiation-induced skin damage.
