The Journal of Practical Medicine ›› 2025, Vol. 41 ›› Issue (22): 3529-3536.doi: 10.3969/j.issn.1006-5725.2025.22.009

• Basic Research • Previous Articles    

Effects of exosomes secreted from mesenchymal stem cells on chondrocyte injury under hypoxia

Shaochu CHEN1,2,Ming GONG2,Wang ZHANG2,Jiawen WU2,Guangxin HUANG3,Yadong ZHANG1()   

  1. *.Department of Spine Surgery (Division 1),Center for Orthopedic Surgery,the Third Affiliated Hospital,Southern Medical University,Guangzhou 510630,Guangdong,China
    *.Department of Spine Surgery,People′s hospital of Longhua,Shenzhen,Shenzhen 518109,Guangdong,China
  • Received:2025-08-01 Online:2025-11-25 Published:2025-11-26
  • Contact: Yadong ZHANG E-mail:zhangyadong6@126.com

Abstract:

Objective To investigate the effects of exosomes derived from hypoxia-treated mesenchymal stem cells on chondrocyte injury. Methods After mesenchymal stem cells were subjected to hypoxic treatment, the secreted exosomes were collected and co-cultured with IL-1β-stimulated chondrocytes. Cell viability was assessed using the CCK-8 assay, while apoptosis was evaluated by flow cytometry and the measurement of Caspase-3 and PARP activities. Intracellular levels of ROS, Fe2+, and MDA were quantified using commercial assay kits. The expression of GPX4, SLC7A11, and ACSL4 was analyzed at both mRNA and protein levels via qRT-PCR and Western blot, respectively. Additionally, the secretion of COL2A1, MMP13, ADAMTS5, TNF-α, IL-6, and PGE2 was determined by ELISA. Results Chondrocyte viability was significantly enhanced following the uptake of exosomes derived from hypoxia-treated mesenchymal stem cells (H-Exo) (P < 0.05). IL-1β treatment reduced chondrocyte viability, increased Caspase-3 and PARP activities, and promoted apoptosis (P < 0.05); however, H-Exo effectively reversed IL-1β-induced apoptotic effects. Furthermore, IL-1β markedly down-regulated the expression of GPX4 and SLC7A11, up-regulated ACSL4 expression, and elevated intracellular levels of ROS, Fe2+, and MDA (P < 0.05), indicating the induction of ferroptosis. Both the ferroptosis inhibitor and H-Exo significantly attenuated IL-1β-triggered ferroptosis, and H-Exo counteracted the detrimental effects of IL-1β as well as those induced by a ferroptosis inducer. Additionally, IL-1β suppressed the expression of the chondrogenic marker COL2A1, up-regulated the catabolic enzymes MMP13 and ADAMTS5, and enhanced the secretion of pro-inflammatory cytokines TNF-α, IL-6, and PGE2 (P < 0.05). Notably, H-Exo alleviated IL-1β-mediated inflammation and restored the balance between chondrogenic anabolism and catabolism. Conclusions Exosomes secreted by mesenchymal stem cells under hypoxic conditions can effectively inhibit chondrocyte apoptosis and ferroptosis, thereby alleviating cellular injury. These findings suggest that such exosomes exert a protective effect on chondrocytes and hold promise as a novel therapeutic strategy for cartilage repair.

Key words: osteoarthritis, cartilage defect, chondrocyte, exosome, ferroptosis

CLC Number: