Wogonoside attenuates the articular cartilage injury and the infiltration of Th1/Th2-type cytokines in papain-induced osteoarthritis in rat model via inhibiting the NF-κB and ERK1/2 activation

Abstract

Objects

Osteoarthritis is the most common joint disease and a major cause of functional limitation and pain in adults. This study aims to investigate the effect of wogonoside (WOG) on the progression of knee osteoarthritis (KOA) in model rats.

Materials and methods

Rats KOA models were established and treated with different doses of WOG (10 mg/kg, 20 mg/kg and 30 mg/kg). The degree of cartilage injury was detected by Mankin scores via HE/Alcian blue staining. The levels of IFN-γ and IL-4 in peripheral blood and synovial fluid and the Th1/Th2 ratio were detected by flow cytometry. The model mice were injected with NF-κB p65 or ERK1/2 inhibitors or activators to further investigate the effect of WOG on KOA.

Results

WOG significantly improved cartilage tissue damage and reduced the Mankins score. WOG down-regulated the level of IFN-γ while up-regulated the expression of IL-4, which maintained the balance of Th1/Th2 cells. Further studies showed that the expression of NF-κB p65, phosphorylated p65, cytoplasmic ERK1/2 and nuclear ERK1/2 were all inhibited by WOG. The results of reverse verification experiments showed that the activator of NF-κB p65 and ERK1/2 weakened the protective effect of WOG on KOA, and the inhibitor of NF-κB p65ERK1/2 enhanced the protective effect of WOG on KOA.

Conclusions

WOG inhibited the activation of NF-κB and ERK1/2 to alleviate the articular cartilage injury and Th1/th2 cytokine infiltration in KOA rats.

Keywords:

• wogonoside
• knee osteoarthritis
• artilage injury
• NF-κB
• ERK1/2

Acknowledgements

The authors give their sincere gratitude to the reviewers for their constructive comments.

Disclosure statement

The authors declare that there are no competing interests associated with the manuscript.