Total glucosides of paeony inhibit the proliferation of fibroblast-like synoviocytes through the regulation of G proteins in rats with collagen-induced arthritis.

The aim of this study was to investigate the expression of G proteins in fibroblast-like synoviocytes (FLSs) from rats with collagen-induced arthritis (CIA) and to determine the effect of total glucosides of paeony (TGP). CIA rats were induced with chicken type II collagen (CCII) in Freund's complete adjuvant. The rats with experimental arthritis were randomly separated into five groups and then treated with TGP (25, 50, and 100mg/kg) from days 14 to 35 after immunization. The secondary inflammatory reactions were evaluated through the polyarthritis index and histopathological changes. The level of cyclic adenosine monophosphate (cAMP) was measured by radioimmunoassay. The FLS proliferation response was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The toxin-catalyzed ADP-ribosylation of G proteins was performed through autoradiography. The results show that TGP (25, 50, and 100mg/kg) significantly decreased the arthritis scores of CIA rats and improved the histopathological changes. TGP inhibited the proliferation of FLSs and increased the level of cAMP. Moreover, the FLS proliferation and the level of Gαi expression were significantly increased, but the level of Gαs expression was decreased after stimulation with IL-1β (10ng/ml) in vitro. TGP (12.5 and 62.5μg/ml) significantly inhibited the FLS proliferation and regulated the balance between Gαi and Gαs. These results demonstrate that TGP may exert its anti-inflammatory effects through the suppression of FLS proliferation, which may be associated with its ability to regulate the balance of G proteins. Thus, TGP may have potential as a therapeutic agent for the treatment of rheumatoid arthritis.

Jia XY ，Chang Y ，Sun XJ ，Wu HX ，Wang C ，Xu HM ，Zhang L ，Zhang LL ，Zheng YQ ，Song LH ，Wei W ... -  《-》

The expression change of β-arrestins in fibroblast-like synoviocytes from rats with collagen-induced arthritis and the effect of total glucosides of paeony.

To investigate the expression of β-arrestins in fibroblast-like synoviocytes (FLS) from collagen-induced arthritis (CIA) rats and the effect of total glucosides of paeony (TGP). TGP and glucosides of tripterygium wilfordii (GTW) were intragastriclly administrated to collagen-induced arthritis (CIA) rats after immunization. The secondary inflammatory reaction was evaluated by hind paw swelling, polyarthritis index and histopathological changes. Antibodies to type II collagen (CII) were determined by enzyme-linked immunosorbent assay (ELISA). Synoviocyte proliferations were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl (MTT) assay. The expression of β-arrestins in synoviocytes from CIA rats was measured by western blot. The administration of TGP (25, 50, 100 mg/kg) depressed hind paw swelling and decreased the arthritis scores of CIA rats. TGP improved the pathologic manifestations of CIA. Serum anti-CII antibodies level increased significantly in CIA rats, while TGP had no effect on it. Fibroblast-like synoviocytes (FLS) proliferation was inhibited by TGP (50, 100 mg/kg). On d14, d28 after immunization, β-arrestins expression greatly up-regulated in synoviocytes from CIA rats and then returned to baseline levels on d42 after immunization. TGP (50, 100 mg/kg) significantly reduced the expression of β-arrestins. An inflammatory process in vivo induces an up-regulation of β-arrestins in synoviocytes from CIA rats while TGP can inhibit this change, which might be one of the important mechanisms for TGP to produce a marked therapeutic effect on RA.

Wang QT ，Zhang LL ，Wu HX ，Wei W ... -  《-》

Effects and mechanisms of total glucosides of paeony on joint damage in rat collagen-induced arthritis.

Zhu L ，Wei W ，Zheng YQ ，Jia XY ... -  《INFLAMMATION RESEARCH》

Effects and mechanisms of total glucosides of paeony on synoviocytes activities in rat collagen-induced arthritis.

Chang Y ，Wei W ，Zhang L ，Xu HM ... -  《JOURNAL OF ETHNOPHARMACOLOGY》

Paeoniflorin inhibits function of synoviocytes pretreated by rIL-1α and regulates EP4 receptor expression.

To investigate the effect of the Paeoniflorin (Pae), a main active component of total glucosides of paeony (TGP) extracted from the root of Paeonia lactiflora, on regulation of synoviocytes cultured from rats collagen-induced arthritis (CIA) in vitro. CIA was induced in male Sprague-Dawley rats immunized with chicken type II collagen (CCII) in Freund's complete adjuvant. The levels of interleukin-1 (IL-1), tumor necrosis factor α (TNF-α), prostaglandin E(2) (PGE(2)) and cyclic adenosine monophosphate (cAMP) were measured by radioimmunoassay. The proliferation responses was determined by the 3-(4,5-2dimethylthiazal-2yl) 2,5-diphenyltetrazoliumbromide (MTT) assay. Expression of E-prostanoid (EP(4)) receptor was detected by Western blotting technique. Treatment of Pae (2.5, 12.5, 62.5 μg/ml) significantly decreased the production of IL-1 and TNF-α. Recombinant interleukin-1 (rIL-1α) (10 ng/ml) apparently stimulated synoviocyte, thymocyte and splenocyte proliferation, and Pae (12.5, 62.5 μg/ml) inhibited abnormal proliferation responses stimulated by rIL-1α. Moreover, rIL-1α time- and concentration-dependently increased production of PGE(2). The production of PGE(2) produced by synoviocytes from CIA rats significantly inhibited by administration of Pae (12.5, 62.5 μg/ml). rIL-1α (10 ng/ml) decreased cAMP of synoviocytes cells treated for 24h. Similarly rIL-1α (0.1, 1, 10 ng/ml) induced a concentration-dependent decrease in the production of cAMP at 24h. Pae (12.5, 62.5 μg/ml) increased the production of cAMP in synoviocytes. The immunoblot, Pae (12.5, 62.5 μg/ml) apparently increased the expression of EP(4) receptor in synoviocytes stimulated by rIL-1α (10 ng/ml). The present study indicates that Pae might exert its anti-inflammatory effects through suppressing synoviocytes function and regulating immune cells responses in CIA rats, which might be associated with its ability to up-regulate the E-prostanoid (EP(4)) receptor protein expression and modulate intracellular cAMP level.

Chang Y ，Zhang L ，Wang C ，Jia XY ，Wei W ... -  《-》