黄芩苷对大鼠类风湿性关节炎软骨损伤的影响

Effects of Baicalin on Cartilage Injury in Rheumatoid Arthritis Rats

【目的】探讨黄芩苷对完全弗氏佐剂(CFA)诱导的大鼠类风湿性关节炎(RA)的治疗作用及机制。【方法】将40只SD大鼠随机分为5组,即假手术组,模型组,黄芩苷低、中、高剂量组,每组8只。除假手术组注射0.1 mL生理盐水外,其余各组大鼠均于右后足垫皮内一次性注射0.1 mL CFA诱导类风湿关节炎大鼠模型。成功造模后,黄芩苷低、中、高剂量组每天在同一时间分别给予对应剂量为25、50、100 mg/kg的黄芩苷(溶于生理盐水配制)灌胃,假手术组和模型组给予等体积生理盐水灌胃,连续给药14 d。采用苏木素-伊红(HE)染色法观察膝关节病理变化,CT扫描测量骨小梁间距,进行碱性磷酸酶(ALP)、骨钙素含量的检测,番红O染色法观察软骨损伤情况,蛋白免疫印迹法检测股骨组织Osx、Col1a1、Dlx-2、白细胞介素(IL)-6、IL-10、Janus激酶1(JAK1)、磷酸化JAK1(p-JAK1)、信号转导转录激活因子3(STAT3)、磷酸化STAT3(p-STAT3)表达水平,酶联免疫吸附分析(ELISA)法检测血清IL-17、IL-23、IL-10的水平。【结果】与假手术组比较,模型组大鼠关节组织出现明显的病理损伤,软骨损伤严重,骨小梁间距显著增宽(P<0.05),ALP、骨钙素含量显著降低(P<0.05),Osx、Col1a1和Dlx-2表达水平显著下调(P<0.05),IL-6、IL-10、IL-17、IL-23细胞因子水平及p-JAK1/JAK1和p-STAT3/STAT3的相对表达量均显著上调(P<0.05);与模型组比较,黄芩苷处理组尤其是高剂量组(100 mg/kg)可显著改善类风湿关节炎大鼠对软骨破坏的炎症反应及滑膜增生,改善软骨损伤,减小骨小梁间距(P<0.05),升高ALP和骨钙素的含量(P<0.05),且明显上调Osx、Col1a1、Dlx-2、IL-10表达水平(P<0.05),下调细胞因子IL-6、IL-17、IL-23的水平及p-JAK1/JAK1和p-STAT3/STAT3的相对表达量(P<0.05)。【结论】黄芩苷可修复CFA诱导的类风湿性关节炎大鼠炎性损伤和骨组织病变,其可能是通过抑制JAK1/STAT3通路激活发挥作用。

Objective To explore the treatment effects of baicalin for rheumatoid arthritis injury induced by complete Freund’s adjuvant(CFA)in rats and its mechanism.Methods Forty SD rats were randomly divided into 5 groups,namely sham-operation group,model group,and low-,middle-,and high-dose groups,8 rats in each group.Apart from the sham-operation group given injection of 0.1 mL of normal saline,the rats of other groups were given one-off intradermal injection of 0.1 mL of CFA into the right hind foot pad to induce into rheumatoid arthritis model.After modeling,the low-,middle-,and high-dose baicalin groups were given intragastric administration of baicalin(dissolved in normal saline)at the dosage of 25,50,100 mg/kg at the same time every day,respectively,and the sham-operation group and model group were given intragastric administration of the same volume of normal saline,the treatment lasting 14 days.The pathological changes in knee joint were observed by hematoxylin-eosin(HE)staining method,trabecular bone spacing was measured by CT scan,contents of alkaline phosphatase(ALP)and osteocalcin in serum were detected,cartilage injury was observed by safranine O staining method,expression levels of Osx,Col1a1,Dlx-2,interleukin(IL)-6,IL-10,Janus kinase 1(JAK1),phosphorylated JAK1(p-JAK1),signal transducers and activators of transcription 3(STAT3),phosphorylated STAT3(p-STAT3)in femur tissue were determined by Western blotting assay,levels of serum IL-17,IL-23,IL-10 were detected by enzyme-linked immunosorbent assay(ELISA).Results Compared with the sham-operation group,the obvious pathological changes in knee joint were seen in the model group,and the trabecular spacing was significantly widened(P<0.05),serum contents of ALP and osteocalcin were significantly reduced(P<0.05),cartilage damage was found,expression levels of Osx,Col1a1 and Dlx-2 were significantly down-regulated(P<0.05),and levels of cytokine IL-6,IL-10,IL-17 and IL-23 and relative expression contents of p-JAK1/JAK1 and p-STAT3/STAT3 were significantly up-regulated(P<0.05).Compared with the model group,the obvious pathological changes in knee joint were improved in the baicalin group,especially in the high-dose baicalin group(100 mg/kg),and the trabecular spacing was significantly reduced(P<0.05),serum contents of ALP and osteocalcin were significantly enhanced(P<0.05),cartilage damage was relieved,expression levels of Osx,Col1a1,Dlx-2 and IL-10 were significantly up-regulated(P<0.05),and levels of cytokine IL-6,IL-17 and IL-23 and relative expression contents of p-JAK1/JAK1 and p-STAT3/STAT3 were significantly down-regulated(P<0.05).Conclusion Baicalin is effective for protecting rats from CFA-induced rheumatoid arthritis injury and bone tissue lesions,and it plays a role of inhibiting activation of JAK1/STAT3 pathway.