Chondroprotective Effect of Wufu Decoction on Tumor Necrosis Factor-α-Induced Chondrocytes via the Extracellular Signal Regulated Kinase 1/2 Signaling Pathway.

Objective: Wufu Decoction (WFD) is a herbal formulation composed of five traditional Chinese herbs that is used clinically for arthritis treatment in China. The current study investigated the chondroprotective effects and the underlying mechanism of WFD for osteoarthritis (OA) therapy.

Methods: The chondroprotective effects of WFD were investigated based on vitro study. Following the successful isolation of chondrocytes from rat cartilage tissues and the identification of collagen II expression with immunofluorescence staining, chondrocytes were co-incubated with tumor necrosis factor-α (TNF-α) to induce an inflammation model; WFD was also administered. After the treatment, cell viability was determined by MTT assay, cell apoptosis was assessed by DAPI staining, the concentration of inflammation cytokines interleukin (IL)-1β and IL-6 were detected with ELISA assay, the expression of collagen II, MEK1/2-ERK1/2 signaling pathway proteins was detected using western blotting, and mRNA expression of MMP-1, MMP-9 and MMP-13 were determined with quantitative real-time polymerase chain reaction.

Results: Wufu Decoction significantly restored the cell viability suppressed by TNF-α and inhibited the cell apoptosis induced by TNF-α in chondrocytes. The high concentrations of IL-1β and IL-6 in TNF-α-induced model cells were significantly decreased in WFD-treated chondrocytes, and the immunofluorescence staining and western blot results showed that the inhibited expression of collagen II in the TNF-α-induced model group was significantly increased in WFD-treated chondrocytes. The protein expressions of MEK1/2, p-ERK1/2, and P53 were significantly reduced in the WFD-treated group compared with those in the model group, and the mRNA expressions of MMP-1, MMP-9, and MMP-13 were also significantly reduced with WFD treatment.

Conclusion: The present study indicated that WFD exerted a chondroprotective effect in TNF-α-induced chondrocytes via the regulation of the ERK1/2 signaling pathway, suggesting that WFD has therapeutic potential for OA therapy.