The Effects Of Taurochenodeoxycholic Acid On Signaling Pathway Of EP₂/EP₄-G-蛋白一cAMP In Adjuvant Arthritis Rats FLSs

Taurochenodeoxycholic Acid (TCDCA) is one of main bioactive substance of animal bile,which showed remarkably inhibition on inflammation. In order to further clarify the molecular machanism of anti-inflammatory effects of TCDCA and search the pharmacological theory about its treatment for RA, AA rats was used in this study to investigate the effect of TCDCA on the signaling pathway which mediated by EP2/EP4,furture clarify the mechanism of anti-arthritis action of TCDCA.This study included:First the FLS from AA rat were cultured in vitro and used ELIS A method to measure the quantity of cAMP, in order to determine dose-response relationship of TCDCA. Second Real time RT-PCR and Western Blot were respectively to determined mRNA and protein expression of EP2/EP4 receptors in FLSs.Third, using Western Blot determined and measured Gas/Gai protein expression In FLSs.Finally ELISA method was used to determine the level of intracellular cAMP analyse EP2/EP4-G protein-cAMP pathway in FLSs.The resule of Elisa method indicated that after TCDCA was administrated, the concentration of cAMP had significantly change in FLS when existence of PGE2 (10"6mol/L), this indicated that the change of cAMP concentration have dependence on concentration of TCDCA. In addition, real-time RT-PCR and Western Blot results shown that PGE2 could promote EP2/EP4 mRNA and protein expression in the FLS, while TCDCA(10-5～10-7mol/L) could significantly reduce the mRNA and protein expression of EP2/EP4 receptors (P<0.01). Except that PGE2 could promote Gi but inbite Gs protein expression,and TCDCA could significantly reduce Gi but promote Gs protein expression.Finally,Compared with the Control group, EP2/EP4 agonists and PDE4 inhibitors significantly increased cAMP of FLSs, and EP2/EP4 blockers, G protein blockers and inhibitors significantly AC after lowering EP2/EP4 agonist treatment FLSs cAMP content. G protein inhibitor+ EP2/EP4 agonist, AC inhibitor+ EP2/EP4 agonist group and EP2/EP4 blocker+ EP2/EP4 agonist, TCDCA of FLSs AA content of cAMP in rats no significant impact.+ EP2/EP4 agonist group compared with PDE4 inhibitors TCDCA can significantly reduce cAMP content of FLSs.Conclusions:Anti-arthritis activity of TCDCA could be mediated via EP2/EP4-G protein-cAMP pathway...