Astragaloside Ⅳ pretreatment of umbilical cord mesenchymal stem cell-derived exosomes intervenes in Nrf2/GPX4 pathway regulation of chondrocytes research on the mechanism of iron death
Zhang Wenhao
Yi Lin
Xiang Wenyuan
Fang Rui
Liang Zhiquan
Abstract：Objective To investigate the impact of Astragaloside Ⅳ(AS-Ⅳ)pretreatment of human umbilical cord mesenchymal stem cell-derived exosomes(hUCMSCs-Exos)on ferroptosis in chondrocytes.Methods Experiments were con-ducted at the Animal Experimental center of Xinjiang Medical University from January 2024 to December 2024,hUCMSCs were pretreated with AS-Ⅳ,followed by the extraction of hUCMSCs-Exos,which were characterized for morphology and size distribution using transmission electron microscopy(TEM)and nanoparticle tracking analysis(NTA).Rat chondrocytes were divided into four groups based on intervention methods:control group(normal chondrocyte culture),model group(IL-1β in-tervention),exosome group(IL-1β+hUCMSCs-Exos intervention),and AS-Ⅳ combined exosome group(IL-1β+AS-Ⅳpretreated hUCMSCs-Exos).Mitochondrial morphology in each group was observed using electron microscopy.Cells were collected by centrifugation,and glutathione(GSH),malondialdehyde(MDA),and reactive oxygen species(ROS)were extrac-ted and quantitatively analyzed.mRNA and protein expression levels of Nrf2 and GPX4 in chondrocytes were detected using RT-qPCR and Western blotting,respectively.Results Exosomes pretreated with AS-Ⅳ exhibited similar vesicular structures and diameters compared to untreated exosomes.Compared to the control group,the model group showed significant mitochon-drial atrophy and membrane rupture.Both the exosome group and the AS-Ⅳ combined exosome group demonstrated im-proved mitochondrial morphology compared to the model group,with the AS-Ⅳ combined exosome group showing more pronounced improvements.The model group exhibited decreased GSH content and increased MDA and ROS levels compared to the control group(t/P=34.851/＜0.001).The exosome group and AS-Ⅳ combined exosome group showed sequentially de-creased GSH content and increased MDA and ROS levels compared to the model group(F/P=6.977/＜0.001;17.249/＜0.001),with the AS-Ⅳ combined exosome group having higher GSH content and lower MDA and ROS levels than the exosome group(t/P=7.744/＜0.001).The model group showed reduced mRNA and protein expression levels of Nrf2 and GPX4 in chondrocytes compared to the control group(t/P=18.871/＜0.001).The exosome group and AS-Ⅳ combined exosome group exhibited sequentially increased mRNA and protein expression levels of Nrf2 and GPX4 compared to the model group(F/P=8.390/＜0.001;4.143/＜0.05),with the AS-Ⅳ combined exosome group showing higher expression levels than the exosome group(t/P=6.912/＜0.05).Conclusion The regulatory effects of AS-Ⅳ pretreated hUCMSCs-Exos on ferroptosis in chondro-cytes may be associated with the upregulation of the Nrf2/GPX4 signaling pathway,thereby inhibiting ferroptotic responses and reducing chondrocyte damage.
Keywords：Knee osteoarthritisAstragaloside ⅣUmbilical mesenchymal stem cellsExosomesFerroptosisNrf2/GPX4 pathwayMechanism
Publication Date：2025-08-18
Online Publishing Date：2025-09-01(First online date of this platform, not the publication date of the document)
Pages：7( 991-997 )