Objectives :The object of this study was to observe the favorable anti arthritic effects of Euiiin-tang(yl̀y˘l nrén-tāng) aqueous extract(EIITe), has been traditionally used in Korean medicine for treating rheumatoid arthritis on collagen induced arthritic(CIA) DBA/1 mice.
Methods :In the present study, effects of EIITe on the releases of human tumor necrosis factor(TNF)-α, interleukin(IL)-1β, matrix metalloproteinase(MMP)-13 and production of Nitric oxide(NO) were observed by in vitro. In addition, to observe the effects on the CIA mice, three different dosages of EIITe, 300, 150 and 150 mg/kg were orally administered once a day for 18 days from 24hrs after antigen challenges(type II collagen) on 21 days after immunization using Type II collagen Freund’s complete adjuvant. Six groups, each of 8 DBA/1 mice per group were used in the present study as follows. Changes on the body weights, macroscopic arthritis scores, splenic weights, splenic TNF-α and IL-6 contents, articular cartilage(femur and tibia) collagen and glycosaminoglycans -chondroitin sulphate, sulphate and hyaluronic acid contents, histopathological observations(microscopic arthritis scores, thicknesses of femur and tibia cartilage thicknesses were monitored, compared to that of dexamethasone, a potent anti inflammatory agents, 1 mg/kg treated mice.
Results :As results of collagen challenges, marked decreases of body weights and gains, articular cartilage collagen and glycosaminoglycan - chondroitin sulphate, sulphate and hyaluronic acid contents were observed with increases of macroscopic arthritis scores, splenic weights, splenic TNF-α and IL-6 contents, articular cartilage(in the both femur and tibia) loss and damages. However, these CIA signs were significantly and dosages dependently inhibited by treatment of EIITe 300 and 150 mg/kg as compared with CIA control, respectively. In addition, the releases of TNF-α, IL-1β, NO and MMP-13 were markedly and dose dependently inhibited by treatment of EIITe, in vitro. Although CIA were more favorably inhibited by treatment of dexamethasone 1 mg/kg as compared with EIITe 300 mg/kg, marked decreases of body weights were detected in dexamethasone 1 mg/kg treated mice.
Conclusions :The results obtained in this study suggest that over 150 mg/kg of EIITe showed favorable anti‐arthritic effects on the CIA mediated by immunomodulatory and/or anti‐oxidative effects. However, detail mechanism studies should be conduced in future with the screening of the biological active compounds in this herb. lthough CIA were more favorably inhibited by treatment of dexamethasone 1 mg/kg as compared with EIITe 300 mg/kg, marked decreases of body weights were detected in dexamethasone 1 mg/kg treated mice, in the present study.