Résumé
OBJECTIVE To investigate the improvement effect and potential mechanism of “Layers adjusting external application” paste on synovial fibrosis （SF） in rats with knee osteoarthritis （KOA）. METHODS Male SD rats were randomly divided into sham operation group， KOA group and Layers adjusting external application group， with 8 rats in each group. KOA model was induced by the anterior cruciate ligament disruption method in KOA group and Layers adjusting external application group. Fourteen days after modeling， the Layers adjusting external application group was given “Layers adjusting external application” paste [Sanse powder （8 g for every 100 cm2）， Compound sanhuang ointment （5 g for every 100 cm2）] on the knee joint， 8 h every day， for 28 d in total. After the last administration， the degree of synovitis and fibrosis in rats was observed， and Krenn scoring was performed in each group. The expressions of collagen Ⅰ， high mobility group protein B1 （HMGB1） and phosphorylated nuclear factor-κB p65 （p-NF-κB p65） were detected in the synovial membrane； the contents of interleukin-1β （IL- 1β）， IL-6 and tumor necrosis factor-α （TNF-α） in serum as well as the expressions of fibrosis-related and HMGB1/Toll-like receptor 4 （TLR4）/NF-κB signaling pathway-related proteins and mRNA were detected in synovial tissue. RESULTS Compared with the sham operation group， the synovial lining cells in the KOA group showed significant proliferation and disordered arrangement， the inflammatory cell infiltration and collagen fiber deposition were obvious； the positive expressing cells of collagen Ⅰ， HMGB1 and p-NF-κB p65 were increased significantly； the contents of IL-1β， IL-6 and TNF-α in serum， the expressions of fibrosis-related protein （transforming growth factor-β， collagen Ⅰ， tissue inhibitor of metalloproteinase 1， α-smooth muscle actin） and their mRNA as well as theexpressions of HMGB1， TLR4 protein and their mRNA， the expressions of p-NF-κB p65 protein and NF-κB p65 mRNA were all increased significantly in synovial tissues of rats （P＜0.01）. Compared with the KOA group， the pathological changes in the synovial tissue of rats in Layers adjusting external application group were significantly improved， and the above quantitative indicators were significantly reversed （P＜0.05 or P＜0.01）. CONCLUSIONS “Layers adjusting external application” paste could significantly improve SF in KOA rats， the mechanism of which may be associated with the inhibition of the activation of HMGB1/ TLR4/NF-κB signaling pathway.
Résumé
Objective:To study the effects of modified citrus pectin (MCP) on the viability and gene expressions of synovial fibroblasts (SF) as well as SF treated by galectin-3 (Gal-3).Methods:Rabbit SF was isolated and cultured in vitro. Then SF was treated with different concentrations of MCP (0, 250, 500, and 750 mg/L). In addition, SF was further treated with the same different concentrations of MCP after treatment with 10 μg/ml Gal-3 for 24 h. The viability of SF was detected by CCK-8 on the first, third, and fifth day after treatment. The mRNA expression of transforming growth factor-β1 (TGF-β1), type I collagen (COL1A2), and Gal-3 in SF was detected by real-time quantitative PCR. The synthesis of type I collagen in SF was investigated by immunofluorescence staining. Results:MCP, especially at a concentration of 500 mg/L can inhibit the proliferation of SF significantly (all P < 0.05) on the first, third, and fifth day after treatment. Compared with the control group, MCP at different concentrations induced different gene expression profiles. In particular, MCP at high concentrations can upregulate the expression of TGF-β1, COL1A2 and Gal-3 in SF. However, MCP shows no significant effect on the synthesis of type I collagen in SF. MCP can down-regulate the expression of TGF-β1, COL1A2, and significantly reduce the synthesis of type I collagen in SF after Gal-3 treatment. Particularly, the effect of MCP at a concentration of 500 mg/L on inhibiting the expression of TGF-β1, COL1A2, and Gal-3 in SF is significant. Conclusions:MCP can inhibit the excessive proliferation of SF and regulate gene expression in SF.