Eucommia ulmoides Oliv polysaccharide reduces the injury of IL-1β-induced chondrocyte by inhibiting NF-κB pathway

Abstract

To investigate the effects of Eucommia ulmoides Oliv polysaccharide on the injury of interleukin-1β(IL-1β)-induced chondrocyte and its possible mechanism. ATDC5 was treated with 10 μg/ml IL-1β to establish osteoarthritis chondrocyte inflammation model, mouse chondrocyte ATDC5 were cultured in vitro and randomly divided into blank group, model group, model+Eucommia ulmoides Oliv polysaccharide low concentration group, model+Eucommia ulmoides Oliv polysaccharide medium concentration group and model+Eucommia ulmoides Oliv polysaccharide high concentration group. The cells in the blank group were cultured with conventional medium;the cells in the model group cells were cultured with a medium containing 10 ?g/ml IL-1β, and the cells in the model+Eucommia ulmoides Oliv polysaccharide low concentration group, model+Eucommia ulmoides Oliv polysaccharide medium concentration group and model+Eucommia ulmoides Oliv polysaccharide high concentration group were co-cultured with medium containing 100, 200, 400 μg/ml Eucommia ulmoides Oliv polysaccharide and 10 μg/ml IL-1β. After the cells of each group were cultured for 24 h, 48 h and 72 h, CCK-8 method was used to detect cell viability. After the cells of each group were cultured for 48 h, flow cytometry and DAPI staining were used to detect cell apoptosis;ELISA method was used to detect the expression of TNF-α, NO, IFN-γ and IL-6 in cells; DCFH-DA method was used to detect the content of ROS in cells;Western blot was used to detect the protein expression of TIMP-1, MMP-13 and NF-κB signaling pathway-related P65 and p-P65;Immunofluorescence staining was used to observe the localization of NF-κB P65 cells. Compared with the blank group, the ATDC5 cell viability and the protein expression of TIMP-1 in the model group reduced (P<0.05), while apoptosis rate, the levels of TNF-α, NO, IFN-γ and IL-6, the content of ROS, the protein expression of MMP-13 and p-P65, and the number of P65+ in the nucleus increased(P<0.05). Compared with the model group, the ATDC5 cell viability and the protein expression of TIMP-1 in the model+Eucommia ulmoides Oliv polysaccharide low concentration group, model+Eucommia ulmoides Oliv polysaccharide medium concentration group and model+Eucommia ulmoides Oliv polysaccharide high concentration group increased (P<0.05), while apoptosis rate, the levels of TNF-α, NO, IFN-γ and IL-6, the content of ROS, the protein expression of MMP-13 and p-P65, and the number of P65+ in the nucleus reduced (P<0.05). The results showed that Eucommia ulmoides Oliv polysaccharide could promote proliferation of IL-1β-induced chondrocyte ATDC5 and inhibit its apoptosis, inflammatory response and matrix degradation. Its mechanism may be related to the inhibition of the activation of NF-κB pathway.