The animals were treated as described in Figure 2. The hind limbs of rats from all groups were examined by HE staining of the ankle joint upon completion of treatment and all behavioral tests. B, bone; C, cartilage; Sp, joint space; Syn, synovial tissue, black arrow, pannus. (A) Original magnification: 50×. (B) Original magnification: 100×. (a) Normal control showed the normal joint structure; (b) there was serious cartilage degradation in vehicle control rats; (c) Aspirin administration reduced the cartilage degradation; (d) Curcumin treatment showed no significant inhibition upon but, (e) FM0807-I (0.1 mmol.l⁻¹)-treated group showed loss of pannus-formation in the cartilage and (f) FM0807-II (0.2 mmol.l⁻¹)-treated group ceased the cartilage degradation. (c) The graph denotes the mean score of cartilage degradation based on the observation and assessed on a semi-quantitative four-point scale (score 0: no destruction; score 1: minimal erosion limited to single spots; score 2: slight to moderate erosion in a limited area; score 3: more extended erosions and score 4: general destruction). Results are presented as mean ± SD. *P<0.05, **P<0.01 vs. the vehicle control; ^###P<0.001 vs. the normal control; ^∇P<0.05, ^∇∇P<0.01 vs. the aspirin group. Data were analyzed using one-way ANOVA, followed by t test.