Figure 6. Melatonin elicited the suppressive effects on NFAT5-amplified inflammation in IL-1β-exposed chondrocytes.

A. Mock- or IL-1β-treated chondrocytes were pretreated with 100 nM siNFAT5 and incubated in serum-free media overnight. NFAT5 protein expression was measured by Western blot. β-actin was used as internal control. B.-G. Chondrocytes were pretreated with 100 nM siNFAT5 for 1 h and then stimulated with or without 10 ng/ml IL-1β for 30 min, followed by incubation with 10 ng/ml melatonin for 24 h. Levels of (B) TNF-α, (C) IL-1β, and (D) PGE₂ in the media were measured by ELISAs. E. NO production was assessed using Griess reagent. F and G. Representative Western blot results (F) and quantification of COX-2 and iNOS expression (G). β-actin was used as internal control. Each value represents means ± SD of 3 replicates or representative of 3 independent experiments. *P < 0.05 compared with control; ^#P < 0.05 compared with IL-1β-treated group; ^§P < 0.05 compared with Siscrb group. Mel: melatonin.