Wu Boyu, Luo Zhiqiang, Chen Zehua, Lu Yifan, Duan Jianhui, Yang Zhuo, Lu Guoliang
Department of Orthopaedics, Dongguan Hospital of Guangzhou University of Chinese Medicine (Dongguan Hospital of Traditional Chinese Medicine), Dongguan 523000, China.
Hunan University of Chinese Medicine, Changsha 410000, China.
Int Immunopharmacol. 2025 Jun 19;162:115111. doi: 10.1016/j.intimp.2025.115111.
Ferroptosis in chondrocytes is increasingly recognized as a key driver of osteoarthritis (OA) progression. Although paeoniflorin (PAE) has demonstrated potent anti-inflammatory and antioxidant properties in multiple disease models, its role in modulating OA through ferroptosis remains unclear.
This study aimed to investigate the protective role of PAE against iron overload-induced OA (IOOA) via the p53/solute carrier family 7 member 11 (SLC7A11)/glutathione peroxidase 4 (GPX4) signaling pathway.
An iron overload model was established in chondrocytes using ferric ammonium citrate for in vitro experiments, while an in vivo IOOA model was induced in mice via destabilization of the medial meniscus combined with iron dextran injection. Subsequent evaluations included cell viability, cartilage matrix metabolism, iron accumulation, oxidative stress markers, and mitochondrial function. To investigate the underlying mechanism, Western blot, immunofluorescence (IF), and Nutlin-3 (a p53 activator) intervention were employed to assess the involvement of the p53/SLC7A11/GPX4 pathway. In vivo assessments included micro-computed tomography imaging, histological analysis, and IF.
PAE significantly improved chondrocyte viability, restored matrix metabolism, reduced iron accumulation and oxidative stress, and protected mitochondrial function under iron overload conditions. Mechanistically, PAE downregulated p53 and upregulated SLC7A11 and GPX4 expression, thereby suppressing ferroptosis. Nutlin-3 partially reversed these protective effects. In vivo, PAE mitigated subchondral bone loss and cartilage destruction, reduced iron deposition, and restored GPX4 and type II collagen (COL2) expression while lowering matrix metalloproteinase 13 (MMP13) levels.
PAE alleviates iron overload-induced OA progression by inhibiting ferroptosis through regulation of the p53/SLC7A11/GPX4 pathway, offering new insights into ferroptosis-targeted OA therapy.
软骨细胞中的铁死亡日益被认为是骨关节炎（OA）进展的关键驱动因素。尽管芍药苷（PAE）在多种疾病模型中已显示出强大的抗炎和抗氧化特性，但其通过铁死亡调节OA的作用仍不清楚。
本研究旨在探讨PAE通过p53/溶质载体家族7成员11（SLC7A11）/谷胱甘肽过氧化物酶4（GPX4）信号通路对铁过载诱导的OA（IOOA）的保护作用。
使用柠檬酸铁在软骨细胞中建立铁过载模型用于体外实验，而通过内侧半月板不稳定联合右旋糖酐铁注射在小鼠体内诱导建立IOOA模型。随后的评估包括细胞活力、软骨基质代谢、铁积累、氧化应激标志物和线粒体功能。为了研究潜在机制，采用蛋白质免疫印迹法、免疫荧光（IF）和Nutlin-3（一种p53激活剂）干预来评估p53/SLC7A11/GPX4通路的参与情况。体内评估包括微型计算机断层扫描成像、组织学分析和IF。
在铁过载条件下，PAE显著提高软骨细胞活力，恢复基质代谢，减少铁积累和氧化应激，并保护线粒体功能。机制上，PAE下调p53并上调SLC7A11和GPX4表达，从而抑制铁死亡。Nutlin-3部分逆转了这些保护作用。在体内，PAE减轻了软骨下骨丢失和软骨破坏，减少了铁沉积，并恢复了GPX4和II型胶原（COL2）表达，同时降低了基质金属蛋白酶13（MMP13）水平。
PAE通过调节p53/SLC7A11/GPX4通路抑制铁死亡，从而减轻铁过载诱导的OA进展，为以铁死亡为靶点的OA治疗提供了新的见解。
