[关键词]
[摘要]
目的 从 NOD 样受体热蛋白结构域 3(NLRP3)/凋亡相关斑点样蛋白(ASC)/半胱氨酸蛋白酶 1(Caspase-1) 轴调控软骨细胞焦亡角度,探讨通络蠲痹颗粒延缓骨关节炎退变的机制。方法 选取 SD 大鼠 50 只随机分为 对照组、模型组、塞来昔布组以及通络蠲痹颗粒低、高剂量组,采用关节腔注射碘乙酸钠溶液诱导大鼠骨关节 炎模型。在造模成功后各组给予相应的通络蠲痹颗粒(4.1、8.2 g·kg-1 )及塞来昔布(0.010 9 g·kg-1 )灌胃,对照 组及模型组灌胃同等体积生理盐水。连续 4 周,每日 1 次。病理染色观察大鼠膝关节软骨组织结构变化;酶联 免疫吸附法(ELISA)检测血清 AST、ALT、KIM-1、α1-MG 的含量;实时荧光定量聚合酶联反应(RT-qPCR)测 定 NLRP3、ASC、半胱氨酸蛋白酶 1(Caspase-1)、气孔蛋白 D(GSDMD)的 mRNA 转录水平;ELISA 法测定白 细胞介素(IL)-1β、IL-6、IL-18、肿瘤坏死因子 α(TNF-α)、基质金属蛋白酶 13(MMP-13)、血小板反应蛋白 基序的去整合素和金属蛋白酶 5(ADAMTS-5)的浓度;免疫组化法及蛋白免疫印迹法观察 NLRP3、ASC、剪切 的半胱氨酸蛋白酶 1(cleaved Caspase-1)、气孔蛋白 D 的 N 端片段(GSDMD-N)的表达;免疫荧光法观察焦亡 关键蛋白 GSDMD-N 与Ⅱ型胶原(collagen Ⅱ)共定位。结果 与对照组比较,模型组大鼠软骨组织出现特征性 病理改变,肝肾功能相关因子 AST、ALT、KIM-1、α1-MG 含量上升,焦亡相关基因 NLRP3、Caspase-1、 ASC、GSDMD mRNA 表达上调,组织炎症水平因子 IL-1β、IL-6、IL-18、TNF-α 及伴随软骨损伤释放的酶 MMP-13、 ADAMTS-5 含 量 升 高 , 焦 亡 相 关 蛋 白 NLRP3、 ASC 蛋 白 表 达 及 cleaved Caspase-1/Caspase-1、 GSDMD-N/GSDMD 比值上调,GSDMD-N、collagen Ⅱ表达增加并存在高度共定位(P<0.01)。与模型组比较, 通络蠲痹颗粒低、高剂量组及塞来昔布组大鼠软骨组织病理损伤有所改善,且 AST、ALT、KIM-1、α1-MG 的 含量下降,NLRP3、Caspase-1、ASC、GSDMDmRNA 表达下调,IL-1β、IL-6、IL-18、TNF-α 含量下降, MMP-13、ADAMTS-5 以及 NLRP3、ASC 蛋白表达及 cleaved Caspase-1/Caspase-1、GSDMD-N/GSDMD 比值均 下调,GSDMD-N、collagen Ⅱ的表达与共定位均减少(P<0.05,P<0.01)。与通络蠲痹颗粒低剂量组比较,通 络蠲痹颗粒高剂量组明显改善软骨损伤,AST、ALT、KIM-1、α1-MG 的含量下降,说明不会随着药物浓度的 升高损伤肝肾组织;NLRP3、Caspase-1、ASC、GSDMD mRNA 表达、IL-1β、IL-6、IL-18、TNF-α 含量、 MMP-13、ADAMTS-5 以及 NLRP3、ASC 蛋白表达及 cleaved Caspase-1/Caspase-1、GSDMD-N/GSDMD 比值均 下调,GSDMD-N、collagen Ⅱ的表达与共定位均减少(P<0.01)。结论 通络蠲痹颗粒可能通过抑制 NLRP3/ ASC/Caspase-1 轴调控软骨细胞焦亡,从而改善大鼠软骨组织的病理损伤状态、降低炎症表达,起到延缓骨关 节炎的作用。
[Key word]
[Abstract]
Objective To investigate the mechanism by which Tongluo Juanbi Granules (TLJB) delays osteoarthritis (OA) degeneration from the perspective of regulating chondrocyte pyroptosis via the NOD-like receptor thermal protein domain-associated protein 3(NLRP3)/apoptosis-associated speck-like protein containing a CARD (ASC)/Caspase-1 axis. Methods Fifty Sprague-Dawley rats were randomly divided into a control group,a model group,low- and highdose TLJB groups,and a celecoxib group. An OA model was induced by intra-articular injection of sodium iodoacetate solution. After successful modeling, the respective groups were administered TLJB granules (4.1, 8.2 g·kg-1 ) or celecoxib (0.010 9 g·kg ⁻¹) by gavage once daily for 4 weeks,while the control and model groups received an equal volume of saline. Pathological staining was used to observe structural changes in the rat knee articular cartilage. Serum levels of AST, ALT, KIM-1, and α1-MG were detected by enzyme-linked immunosorbent assay (ELISA). The mRNA transcription levels of NLRP3,ASC,Caspase-1,and gasdermin D (GSDMD) were measured using real-time quantitative polymerase chain reaction (RT-qPCR). The concentrations of interleukin (IL)-1β,IL-6,IL-18,tumor necrosis factor-α(TNF-α),matrix metalloproteinase-13(MMP-13),and a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5) were determined by ELISA. The expression of NLRP3, ASC, cleaved Caspase-1, and the N-terminal fragment of GSDMD (GSDMD-N) was observed via immunohistochemistry and Western Blot. Co-localization of the key pyroptosis protein GSDMD-N with collagen type Ⅱ(collagen Ⅱ) was assessed by immunofluorescence. Results Compared with the control group,the model group showed characteristic pathological changes in cartilage tissue,increased serum levels of liver and kidney function-related factors (AST,ALT,KIM-1, α1-MG), upregulation of pyroptosis-related gene mRNA expression (NLRP3, Caspase-1, ASC, GSDMD), elevated levels of tissue inflammatory factors (IL-1β, IL-6, IL-18, TNF- α) and cartilage damage-associated enzymes (MMP-13,ADAMTS-5),increased expression of pyroptosis-related proteins NLRP3 and ASC,elevated cleaved Caspase-1/Caspase-1 and GSDMD-N/GSDMD ratios, and enhanced expression and high co-localization of GSDMD-N and collagen II (all P<0.01). Compared with the model group,the low- and high-dose TLJB groups and the celecoxib group exhibited ameliorated pathological cartilage damage,decreased levels of AST,ALT,KIM-1,and α1-MG,downregulated mRNA expression of NLRP3,Caspase-1,ASC,and GSDMD,reduced levels of IL-1β, IL-6,IL-18,TNF-α,MMP-13,and ADAMTS-5,decreased expression of NLRP3 and ASC proteins,lowered cleaved Caspase-1/Caspase-1 and GSDMD-N/GSDMD ratios, and diminished expression and co-localization of GSDMD-N and collagen II (P<0.05,P<0.01). Compared with the low-dose TLJB group,the high-dose TLJB group demonstrated significantly improved cartilage damage and further reductions in AST, ALT, KIM-1, and α1-MG levels, indicating no hepatorenal tissue damage with increased concentration. Additionally, the high-dose group showed downregulated mRNA expression of NLRP3, Caspase-1, ASC, and GSDMD; decreased levels of IL-1β, IL-6, IL-18, TNF- α, MMP-13, and ADAMTS-5; reduced expression of NLRP3 and ASC proteins; lowered cleaved Caspase-1/Caspase-1 and GSDMD-N/GSDMD ratios; and diminished expression and co-localization of GSDMD-N and collagen Ⅱ(all P<0.01). Conclusion TLJB may alleviate pathological cartilage damage and reduce inflammatory expression,thereby delaying osteoarthritis progression,potentially through inhibiting the NLRP3/ASC/ Caspase-1 axis to regulate chondrocyte pyroptosis.
[中图分类号]
R285.5
[基金项目]
国家自然科学基金项目(82405447);湖南省自然科学基金项目(2024JJ8125,2023JJ60118)。