目的 探讨益气续骨合剂通过 Nrf2/GPX4 信号通路介导铁死亡对膝骨关节炎（KOA）的影响及机制。 方法 体内实验采用前交叉韧带离断（ACLT）法构建 SD 大鼠膝骨关节炎模型，益气续骨合剂灌胃后取材，采 用病理组织学染色观察软骨组织形态改变，采用免疫组化法观察大鼠软骨组织中 Nrf2、GPX4、SLC7A11、 ACSL4 表达，透射电镜观察软骨细胞超微结构。体外实验采用 SD 大鼠软骨细胞，叔丁基过氧化氢（TBHP）诱 导铁死亡模型，加入益气续骨合剂含药血清干预后，采用 CCK-8、EDU 荧光染色检测软骨细胞活力，DCFHDA 荧光探针检测软骨细胞 ROS 水平，免疫荧光检测软骨细胞 Nrf2、GPX4 的表达水平，JC-1 检测软骨细胞线 粒体膜电位，生化试剂盒检测软骨细胞 Fe2+ 、MDA、GSH 水平，RT-qPCR 及 Western Blot 法检测软骨细胞 Nrf2、GPX4、SLC7A11、ACSL4、CollagenⅡ、Aggrecan mRNA 和蛋白的表达水平。结果 体内实验结果显 示，与模型组比较，益气续骨合剂可显著减轻软骨细胞线粒体损伤，改善 SD 大鼠膝骨关节炎模型软骨组织损 伤，降低 Mankin 评分（P＜0.05，P＜0.01）；上调软骨组织中 Nrf2、GPX4、SLC7A11 的表达（P＜0.05，P＜ 0.01），下调 ACSL4 的表达（P＜0.05，P＜0.01）。体外实验结果显示，与模型组比较，益气续骨合剂含药血清 可提高软骨细胞活力（P＜0.05，P＜0.01），下调软骨细胞 ROS、Fe2+ 、MDA 水平（P＜0.01），上调 GSH 水平 （P＜0.01），恢复软骨细胞线粒体膜电位（P＜0.01），上调 Nrf2、GPX4、SLC7A11、CollagenⅡ、Aggrecan mRNA 和蛋白的表达（P＜0.05，P＜0.01），下调 ACSL4 mRNA 和蛋白的表达（P＜0.01）。结论 益气续骨合剂 可能通过激活 Nrf2/GPX4 信号通路抑制软骨细胞铁死亡缓解膝骨关节炎软骨损伤。

Objective To investigate the effects and mechanism of Yiqi Xugu Mixture on knee osteoarthritis （KOA） through the Nrf2/GPX4 signaling pathway-mediated ferroptosis. Methods For the in vivo experiment，a KOA model was established in SD rats using the anterior cruciate ligament transection （ACLT） method. After intragastric administration of Yiqi Xugu Mixture，cartilage tissues were harvested. Histopathological staining was used to observe morphological changes in cartilage tissue； immunohistochemistry was employed to detect the expression of Nrf2， GPX4， SLC7A11， and ACSL4 in rat cartilage； and transmission electron microscopy was used to observe the ultrastructure of chondrocytes. For the in vitro experiment，chondrocytes from SD rats were used. A ferroptosis model was induced using tert-butyl hydroperoxide （TBHP）. After intervention with the drug-containing serum of Yiqi Xugu Mixture，cell viability was assessed by CCK-8 assay and EDU fluorescent staining；ROS levels in chondrocytes were detected using the DCFH-DA fluorescent probe；immunofluorescence was used to examine the expression levels of Nrf2 and GPX4 in chondrocytes； mitochondrial membrane potential was measured with JC-1 staining； biochemical kits were used to determine Fe2+ ，MDA，and GSH levels in chondrocytes；and RT-qPCR and Western Blot were performed to measure the mRNA and protein expression levels of Nrf2，GPX4，SLC7A11，ACSL4，CollagenⅡ，and Aggrecan in chondrocytes. Results The in vivo results showed that， compared with the model group， Yiqi Xugu Mixture significantly alleviated mitochondrial damage in chondrocytes， improved cartilage tissue injury in the SD rat KOA model， and reduced the Mankin score （P＜0.05， P＜0.01）. It upregulated the expression of Nrf2， GPX4， and SLC7A11 in cartilage tissue （P＜0.05，P＜0.01） and downregulated the expression of ACSL4（P＜0.05，P＜0.01）. The in vitro results demonstrated that， compared with the model group， the drug-containing serum of Yiqi Xugu Mixture increased chondrocyte viability （P＜0.05，P＜0.01），downregulated the levels of ROS，Fe2+，and MDA in chondrocytes （P＜0.01）， upregulated GSH levels （P＜0.01）， restored mitochondrial membrane potential in chondrocytes （P＜0.01），upregulated the mRNA and protein expression of Nrf2，GPX4，SLC7A11，Collagen Ⅱ， and Aggrecan （P＜0.05， P＜0.01）， and downregulated the mRNA and protein expression of ACSL4（P＜0.01）. Conclusion Yiqi Xugu Mixture may alleviate cartilage injury in knee osteoarthritis by inhibiting chondrocyte ferroptosis through activation of the Nrf2/GPX4 signaling pathway.

R285.5

国 家 自 然 科 学 基 金 项 目（82360943）； 云 南 省 科 技 厅 项 目（202101AZ070001-170， 202301AZ070001-094， 202301AZ070001-15， 202501AZ070001-018，202501AZ070001-117）；云南省基础研究专项（202501AU070167）；云南省临床医学中心科研项目（2024YNLCYXZX0293）。