Fig. 1

Nutlin-3 attenuated arthritis and decreased IL-6 production in Lewis AIA rats. Lewis rats were immunized with complete Freund’s adjuvant, and received Nutlin-3, dimethyl sulfoxide (DMSO), or phosphate-buffered saline (PBS) from day 8 to day 12 after immunization. Arthritis scores were assessed every 3 days. a The mean arthritis scores. Nutlin significantly decreased arthritis, compared to DMSO (p = 0.16 and 0.02, respectively, on day (d)13 and day 21). b Severity of inflammation was calculated by subtracting the volume of hind paw swelling between day 21 and day 8 after immunization (p = 0.04, Nutlin versus DMSO) and the body weight of the Nutlin group has a tendency to increase (p = 0.14, Nutlin versus DMSO). c Interleukin-6 (IL-6) levels in the serum of the Nutlin group were significantly decreased compared to those in the DMSO and PBS groups (p = 0.01 and 0.04, respectively). d IL-6 level in the joint (p = 0.09, Nutlin versus DMSO; p = 0.19, Nutlin versus PBS). e Nutlin-3 decreased infiltration of inflammatory cells into the synovial tissue and bone erosion in AIA rats. Infiltration of inflammatory cells into the synovial tissue and pannus formation were observed in DMSO and PBS group, but not in the Nutlin group. *p < 0.01