Therapeutic Effects And Mechanisms Of Combination Therapy Of Benzoylaconine And Paeoniflorin In Rheumatoid Arthritis

Objective: To make clear the anti-inflammatory and analgesic effects of different combination therapy of benzoylaconine and paeoniflorin,and to investigate the therapeutic effects and possible mechanisms involved in the combination therapy of benzoylaconine and paeoniflorin in rheumatoid arthritis.Methods: 1.In order to research the anti-inflammatory and analgesic effects of different combination therapy and to identify the optimal dosage,the xylene induced auricles swelling model,the paws swelling test of rats caused by egg white,the hot-plate test and acetic acid induced writhing model were applied.2.Collagen-induced arthritis(CIA)model was used to evaluate the therapeutic effects of the combination therapy of benzoylaconine and paeoniflorin on rheumatoid arthritis by assessing the paw swelling and arthritis index(AI),examining the pathological injuries of ankle,spleen and thymus by HE staining,and measuring the indexes of spleen and thymus.3.Related makers were detected such as the levels of PGE2,Cytokine(IL-1?,IL-6,IL-10,TNF-?,and VEGF),Ig G,anti-C? antibody,and MMP-3 in serum by ELISA,the expressions of STAT1 and STAT3 in synovium of ankle joint were determined by immunohistochemistry staining,the ultramicrostructure of synovial cell was observed by transmission electron microscopy so as to explore the mechanisms of combination therapy of benzoylaconine and paeoniflorin in rheumatoid arthritis.Results: 1.The auricles swelling in mice were remarkably suppressed in combination therapy of benzoylaconine and paeoniflorin(high-dose combination group)(P<0.05);the paws swelling in rats was remarkably inhibited in combination therapy of benzoylaconine and paeoniflorin(high-dose combination group)(P<0.05).Compared with paeoniflorin group and high-dose benzoylaconine group,the paws swelling in rats was significantly relieved in high-dose combination group(P<0.05).The pain threshold of mice induced by hot-plate and acetic acid was markedly elevated in combination therapy of benzoylaconine and paeoniflorin(high-dose combination group)(P<0.05).Furthermore,the study indicated that the number of writhing induced by acetic acid in mice was significantly reduced in combination therapy of benzoylaconine and paeoniflorin(P<0.01).Compared with paeoniflorin group and high-dose benzoylaconine group,the number of writhing in mice was remarkably decreased in high-dose combination group(P<0.01).2.The paws swelling and arthritis index in rats were significantly attenuated in combination therapy of benzoylaconine and paeoniflorin(combination group),paeoniflorin group and benzoylaconine group(P<0.05).Moreover,there was a decreasing trend of the paws swelling and arthritis index in combination group compared with the single drug treatment group.The synovial hyperplasia,pannus formation,inflammatory cell infiltration and mild bone destruction were effectively alleviated,and joint pathology score of CIA rats was significantly decreased in combination group and benzoylaconine group(P<0.01).In addition,joint histopathological score in rats in combination group was lower than that in single drug treatment group.3.The present study showed that the levels of PGE2,IL-1?,TNF-?,VEGF and Ig G in serum were decreased significantly in combination group(P<0.05).The levels of TNF-? in serum in paeoniflorin group(P<0.05),IL-1? and TNF-? in benzoylaconine group(P<0.05)were remarkably decreased.The level of serum IL-1? in combination group was significantly lower than that in paeoniflorin group(P<0.05).The expressions of STAT1 and STAT3 in synovium of CIA rats in combination group and benzoylaconine group were both significantly inhibited(P<0.05),and they were lower in combination group than that in single drug treatment group.The heterochromatin shrinkage of synovial cell nuclear,the dilation of rough endoplasmic reticulum and the swelling of mitochondria could be attenuated in CIA rats treated with combination therapy,while the decreasing number of dense bodies,golgi apparatus and mitochondria could be found.Conclusion: Compared with monotherapy of benzoylaconine or paeoniflorin treatment,there is more obvious anti-inflammatory and analgesic effect in combination therapy of benzoylaconine and paeoniflorin owing to synergistic action.Combination therapy of benzoylaconine and paeoniflorin in the treatment of RA has better effect than monotherapy.The possible mechanisms may be related to the inhibition of immune proliferation and the production of serum PGE2 or Ig G,the regulation of serum cytokine(IL-1?,TNF-? and VEGF),the regulation of the expressions of STAT1 and STAT3 in JAK/STAT signal Pathway and the suppression of the abnormal secretion and proliferation of synovial cells.