Fig. 1

Therapeutic roles of SKN on collagen-induced arthritis (CIA) mice. CIA mice were intragastric administered with 4 mg/kg SKN, or vehicle for 20 days from the day of booster immunization. A Macroscopic measurement of arthritis like erythema or swelling was assessed in mice paws of all groups. B HE staining images of metatarsophalangeal joint sections of each group. C Arthritis score was evaluated with a scale of 0–4 for each paw, and a possible maximum score of 16 for each mouse. D Arthritis incidence rate are the positive number/total number in every group. E The evaluated and analyzed histological scores of each group. The data is expressed as an average ± SEM (n = 6). *P < 0.05, **P < 0.01, ***P < 0.001, compared with the CIA group