水飞蓟宾调控TLR4/NF-κB通路介导的细胞凋亡改善膝骨性关节炎模型大鼠软骨损伤

Regulation of cell apoptosis by Silybinin targeting the TLR4/NF-κB pathway improves cartilage injury in a rat model of knee osteoarthritis

目的观察水飞蓟宾(silybinin,SB)对膝骨性关节炎(knee osteoarthritis,KOA)模型鼠软骨损伤的作用,并探讨其对Toll样受体4(Toll-like receptor 4,TLR4)/核因子κB(NF-κB)通路和细胞凋亡的影响。方法选取SD大鼠作为本研究的对象,并将其分为正常对照组、模型组、SB组,每组各8只,一共24只。采用木瓜蛋白酶关节腔注射构建KOA大鼠模型并进行SB干预6周后,截取大鼠膝关节,苏木精-伊红染色法和番红-固绿染色法观察各组组织病理学变化,并采用国际骨关节炎研究协会(osteoarthritis research society international,OARSI)评分标准进行组织学评分;Western Blot检测TLR4、NF-κB、p65、BAX、BCL-2、Caspase-3蛋白表达变化。结果模型组膝关节软骨组织OARSI评分与正常对照组相比明显升高(P<0.0001);同时,检测发现软骨组织中TLR4、NF-κB、p65、BAX、Caspase3蛋白表达水平明显升高,相反抗凋亡蛋白BCL-2的表达水平则明显降低(P<0.0001)。与模型组相比,SB组关节软骨组织OARSI评分明显降低(P<0.001)。结论水飞蓟宾通过抑制软骨下骨中TLR4/NF-κB通路的激活来抑制细胞凋亡的发生,从而修复KOA模型大鼠损伤的关节软骨。

Objective To investigate the effect of silybinin(SB)on cartilage injury in a rat model of knee osteoarthritis(KOA)and explore its impact on the Toll-like receptor 4(TLR4)/nuclear factor-κB(NF-κB)pathway and cell apoptosis.Methods SD rats were divided into a normal control group,model group,and SB group,with 8 rats in each group(total n=24).The KOA model was established by intra-articular injection of papain,followed by 6 weeks of SB intervention.Histological changes were observed using safranin O-fast green and hematoxylin-eosin staining,and histological scoring was performed using the Osteoarthritis Research Society International(OARSI)scoring system.Western blot was used to detect the expression changes of TLR4,NF-κB,p65,BAX,BCL-2,and Caspase-3 proteins.Results The OARSI score of the knee joint cartilage tissue in the model group was significantly higher than that in the normal control group(P<0.0001).Additionally,the levels of TLR4,NF-κB,p65,BAX,and Caspase3 proteins in the subchondral bone tissue of the model group were significantly increased,while the expression level of the anti-apoptotic protein BCL-2 was significantly decreased(P<0.0001).Compared with the model group,the OARSI score of the joint cartilage tissue in the SB group was significantly lower(P<0.001),and the expression levels of TLR4,NF-κB,p65,BAX,and Caspase3 proteins in the subchondral bone tissue were significantly downregulated,while the expression level of BCL-2 was significantly upregulated(P<0.0001).Conclusion Silybinin inhibits cell apoptosis by suppressing the activation of the TLR4/NF-κB pathway in subchondral bone,thereby repairing cartilage injury in the rat model of KOA.