The protective effect of Dendrobium officinale polysaccharides on photoaging fibroblasts by scavenging reactive oxygen species and promoting the expression of TGFβ1

The purpose of this study was to explore the protective effect of Dendrobium officinale polysaccharides (DOP) on photoaging human skin fibroblasts and its specific mechanism of action. The photoaging fibroblast model was established by ultraviolet B (UVB) irradiation. The toxic effects of different concentrations of DOP were detected using MTT. Senescent cells were detected using a βgalactosidase kit. Reactive oxygen species (ROS) in cells were detected using a flow cytometer. The expression of matrix metalloproteinase1 (MMP1), type I collagen Cterminal peptide (CICP), and transforming growth factor β1 (TGFβ1) in spent culture medium was detected by ELISA. The results showed that the low concentration of DOP (20, 40, 80 μg/mL) had no cytotoxicity on fibroblasts. After 60 mJ/cm2 UVB irradiation, the number of aging βgalpositive cells increased, the levels of CICP and TGFβ1 in spent culture medium decreased, while the levels of MMP1 and ROS increased. After administration of DOP on photoaging fibroblasts, the number of aging βgalpositive cells decreased, the levels of ROS and MMP1 decreased, and the levels of TGFβ1 and CICP increased. This experiment suggests that DOP has the effect of removing ROS induced by UVB, regulating the balance of collagen production and degradation, and protecting photoaging human skin fibroblasts.