史纪元　姬乐　武世勋　刘时璋　易智　傅蔷

摘要 目的：考察淫羊藿苷在治療骨关节炎中的潜在价值，以及淫羊藿苷对核苷酸结合寡聚化结构域样受体蛋白3（NLRP3）炎性小体和半胱天冬酶-1（Caspase-1）的调控作用。方法：本研究通过脂多糖（LPS）诱导大鼠膝关节软骨细胞建立体外骨关节炎模型，通过碘乙酸单钠处理SD大鼠建立体内骨关节炎模型。通过乳酸脱氢酶漏出实验检测细胞毒性，通过MTT实验检测细胞活力。通过qRT-PCR检测NLRP3 mRNA的表达，通过Western Blotting检测NLRP3、IL-1β、IL-18、MMP-1、MMP-13、Collagen Ⅱ、Caspase-1、ASC和GSDMD的蛋白表达。用免疫荧光法和免疫组化法检测软骨细胞和大鼠软骨中的NLRP3表达;番红O/固绿染色评价大鼠软骨病变。结果：与LPS组比较，LPS+ICA组LDH的漏出率、IL-1β、IL-18、MMP-1、MMP-13、NLRP3、Caspase-1、ASC和GSDMD的表达水平明显降低，而Collagen Ⅱ明显升高（P<0.05）。与LPS+ICA+pcDNA3.1-NC组比较，LPS+ICA+pcDNA3.1-NLRP3组的乳酸脱氢酶漏出率及NLRP3炎性小体相关蛋白表达水平明显升高（P<0.05）。与对照组比较，OA组大鼠软骨组织中NLRP3阳性细胞数量显著增加，而OA+ICA组的NLRP3阳性细胞数量明显降低（P<0.05）。与OA组比较，OA+ICA组的NRLP3、IL-1β、IL-18、MMP-1、MMP-13、Caspase-1、ASC和GSDMD的蛋白表达水平明显降低，而Collagen的蛋白表达水平明显升高（P<0.05）。结论：淫羊藿苷通过抑制NLRP3和Caspase-1信号转导来抑制脂多糖诱导的软骨细胞损伤和细胞焦亡，从而减轻大鼠骨关节炎。

关键词 骨关节炎;淫羊藿苷;细胞焦亡;NLRP3炎性小体;半胱天冬酶-1;软骨;脂多糖;乳酸脱氢酶

Abstract Objective：To investigate the potential value of icariin in the treatment of osteoarthritis and the regulatory effect of Icariin on nucleoside binding oligomerization domain like receptor protein 3（NLRP3） and caspase-1.Methods：In this study，lipopolysaccharide（LPS） was used to induce rat knee chondrocytes to establish an in vitro osteoarthritis model，and SD rats were treated with monosodium iodoacetate to establish an in vivo osteoarthritis model.The cytotoxicity was detected by the lactate dehydrogenase leakage test，and the cell viability was detected by the MTT test.The expression of NLRP3 mRNA was detected by qRT-PCR，and the protein expression of NLRP3，IL-1β，IL-18，MMP-1，MMP-13，collagen Ⅱ，Caspase-1，ASC and GSDMD was detected by Western Blotting.Immunofluorescence and immunohistochemical methods were used to detect the expression of NLRP3 in chondrocytes and rat cartilage.Safranin O/Fast Green staining evaluated cartilage lesions in rats.Results：Compared with LPS group，the LDH leakage rate and the expression levels of IL-1β，IL-18，MMP-1，MMP-13，NLRP3，Caspase-1，ASC，and GSDMD in LPS+ICA group were significantly reduced，while collagenⅡ was increased（P<0.05）.Compared with the LPS+ICA+pcDNA3.1-NC group，the lactate dehydrogenase leakage rate and the expression level of NLRP3 inflammasome-related protein in the LPS+ICA+pcDNA3.1-NLRP3 group were significantly increased（P<0.05）.Compared with the control group，the number of NLRP3 positive cells in the cartilage tissue of the OA group increased significantly，while the number of NLRP3 positive cells in the OA+ICA group was significantly reduced（P<0.05）.Compared with the OA group，the protein expression levels of NRLP3，IL-1β，IL-18，MMP-1，MMP-13，Caspase-1，ASC and GSDMD in the OA+ICA group were significantly reduced，while the protein expression levels of collagen Ⅱ were significantly increased（P<0.05）.Conclusion：Icariin inhibits lipopolysaccharide-induced chondrocyte damage and pyrolysis by inhibiting NLRP3 and Caspase-1 signaling，thereby reducing osteoarthritis in rats.

Keywords Osteoarthritis; Icariin; Pyroptosis; NLRP3 inflammatory corpuscle; Caspase-1; Cartilage; Lipopolysaccharide; Lactate dehydrogenase

中图分类号：R284;R684文献标识码：Adoi：10.3969/j.issn.1673-7202.2021.18.009

骨关节炎（Osteoarthritis，OA）是一种常见的慢性退行性关节骨疾病，主要特征是关节僵硬和软骨退化。随着人口老龄化的加剧，OA的发病率逐年升高。目前，OA的药物治疗效果并不理想，因此需要开发更安全、耐受性更好的OA治疗药物[1]。软骨病变在OA的发展过程中扮演重要角色，包括氧化应激、炎症反应、细胞凋亡、软骨基质损失和自噬。动物模型的研究表明，生长因子（如TGF-β和Wnt3a）以及信号分子（如β-catenin、Smad3和HIF-2α）均参与OA的发展[2-4]。此外，炎症和细胞外基质（ECM）的丢失被认为是OA软骨损伤的重要驱动因素[5]。了解这些因素的变化规律可能为OA提供有效的治疗方法。

细胞焦亡（Pyroptosis）是抑制依赖于半胱天冬酶-1（Caspase-1）且伴有炎症介质释放的程序性细胞死亡。……