Rhodojaponin II inhibits TNF‐α‐induced inflammatory cytokine secretion in MH7A human rheumatoid arthritis fibroblast‐like synoviocytes
Lingli Kong, Laifang Wang, Qing Zhao, Guijuan Di, Huiqiang Wu
Abstract
Rhodojaponin II (R-II) has been shown to possess anti-inflammatory activity. Herein, we aimed to explore the effect of R-II on tumor necrosis factor-α (TNF-α)-induced inflammation in MH7A rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLSs). We found that R-II treatment at high concentration suppressed the viability of MH7A cells. R-II suppressed the levels of nitric oxide and prostaglandin E2, and inhibited messenger RNA expression and concentrations of interleukin-1β (IL-1β), IL-6 and matrix metalloproteinase-1 in TNF-α-stimulated RA-FLSs. Additionally, R-II repressed TNF-α-induced activation of the Akt, nuclear factor-κB (NF-κB), and toll-like receptor 4 (TLR4)/MyD88 pathways in MH7A cells. Inhibition of the Akt, NF-κB, and TLR4/MyD88 pathways by the corresponding inhibitors reinforced the inhibitory effect of R-II on TNF-α-induced inflammatory cytokine secretion in MH7A cells. R-II ameliorated the severity of collagen-induced arthritis in mice by inhibiting inflammation. In conclusion, R-II repressed TNF-α-induced inflammatory response in MH7A cells by inactivating the Akt, NF-κB, and TLR4/MyD88 pathways.