Effects of daphnetin on mRNA of TLR2,TLR4,and TLR9 in collagen-induced arthritis rats

This study is aimed to investigate the expression of TLR2,TLR4,and TLR9 mRNA in spleen leukomonocyte cells from CIA rat and the effects of daphnetin on the genes.Wistar rats were immunized with bovine-derived type II collagen(CII) to construct CIA model.The daphnetin treated groups were intraperitoneally injected with different dose of daphnetin,while CIA model group and healthy group were intraperitoneally injected with the equal volume of sterile saline in the same way.The TLR2,TLR4,and TLR9 mRNA of spleen leukomonocyte cells from each group were detected by real time PCR.We found that the immunized paw showed obvious swelling after immunization.In contrast to CIA model group,significant relief was found in immunized paw of daphnetin treated group.The expressions of TLR2,TLR4,and TLR9 mRNA in daphnetin treated group and healthy group was obviously lower than those of CIA model group(P 0.05).The expression of TLR2,TLR4,TLR9 mRNA showed no significant difference between daphnetin high dose group and healthy group(P 0.05).In conclusion,TLR2,TLR4,and TLR9 are associated with morbidity of RA,while daphnetin could down-regulate the expressions of TLR2,TLR4,and TLR9 mRNA in CIA.