Figure 4.

Glycyrrhizin suppressed nitrite and prostaglandin E2 (PGE₂) production in chondrocytes. Cells were co-treated with glycyrrhizin (5 mM) and interleukin-1β (IL-1β; 10 ng/mL) for 24 hours. si-HMGB1 was transfected into osteoarthritis patients’ chondrocytes 6 hours before the stimulation. (A) PGE₂ levels determined by ELISA (n = 6). (B) Nitrite production (n = 6). All the experiments were repeated independently 3 times. **P < 0.01, ***P < 0.001 compared with normal controls (NC). ^#P < 0.05, ^##P < 0.01 compared with single IL-1β treatment.