Fig. 2

Osthole inhibits inflammation and oxidative stress in collagen-induced arthritis rat model. a Histological analysis was performed using rat hind paw sections stained with HE (scale bars 50 μm). b Histopathologic severity was assessed and calculated. c Levels of IL-1β, TNF-α and IL-6 in serum were measured by ELISA. Serum levels of several oxidative stress indicators, including iNOS concentrations (d), GPx activities (e), MDA concentrations (f) and SOD activities (g), were determined by assay kits. Values are expressed as the mean ± SD. **p < 0.01 compared with the normal control group, ^#p < 0.05, ^##p < 0.01 compared with the CIA group