Fig. 8

SKN inhibits the activation of JAK/STAT pathway in TNF-α-induced FLS and CIA mice. FLS for p-JAK1, p-STAT1 and p-STAT6 were starved for 48 h in 10% FBS medium, pretreated with SKN for 2 h,and then stimulated with 20 ng/ml TNF-α for 15 min before collection. The phosphorylations of JAK1 (A), STAT1 (B), and STAT6 (C) in FLS were measured by western blot. From the day of intensive immunization, CIA mice were given 4 mg/kg SKN and 0.5 mg/kg MTX for 20 consecutive days. The levels of p-JAK1 (D), p-STAT1 (E), and p-STAT6 (F) in joint of CIA mice treated with SKN were analyzed by western blot, too. The experiments were carried out in triplicate indenpendently and calculated Mean ± SEM (n = 3 for in vitro assays, n = 6 for in vivo assays). ***P < 0.001, **P < 0.01, and *P < 0.05, compared with the CIA/TNF-α-induced group; ^##P < 0.01, ^###P < 0.001, compared with the control group