Figure 1

Effect of HDACi ITF2357 on SWC-induced arthritis. (A,B) Joint inflammation was induced by injection of 25 µg SCW fragments into the right knee joint of C57/Bl6 mice 2 h after ITF2357 was orally supplied (n = 5 mice per group). Joint swelling was determined by 99mTc-uptake method (30) at day 1 (A) and day 2 (B). Mice were treated with vehicle, 1 and 10 mg/kg ITF2357. Note the suppression of joint swelling at day 2 by both 1 and 10 mg/kg ITF2357. (C) At day 2 chondrocyte proteoglycan (PG)-synthesis was analyzed by using 35S-sulphate incorporation method (31). Treatment with ITF2357 (10 mg/kg/day) almost restored (−13%) the chondrocyte PG-synthesis when compared with vehicle (−44%). (D) Vehicle treatment showed clear cell influx (predominantly PMNs) in the joint cavity and synovial lining layer (see arrows). After treatment with 10 mg/kg ITF2357, reduced cell influx in the joint cavity was seen. P = patella, F = femur, JC joint cavity. Mann-Whitney U test was used for statistical analysis. *P < 0.05.