Fig. 2

IPA suppressed the production of the inflammatory factors. A–C Content of IL-6, TNF-α and PGE2 in the cell suspension was detected by ELISA (n = 5). D Content of NO was detected by the Griess reaction (n = 5). E–G Content of IL-6, TNF-α and PGE2 in the rat serum was detected by ELISA (n = 5). H–K RT-qPCR analysis of IL-6, TNF-α, iNOS and COX-2 in chondrocytes (n = 9). L–N Western blot and semi-quantitative analysis of iNOS and COX-2 (n = 3). ^*p < 0.05, ^**p < 0.01 vs. the control group, ^#p < 0.05, ^##p < 0.01 vs. the IL-1β group