Qiu Mingjun, Xie Yanhua, Tan Guanghua, Wang Xiaoxu, Huang Peiguan, Hong Liang
Department of joint surgery, The Second Affiliated Hospital of University of South China, China.
Department of orthopedic, The Second Affiliated Hospital of University of South China, China.
Heliyon. 2024 Jan 3;10(2):e24042. doi: 10.1016/j.heliyon.2024.e24042. eCollection 2024 Jan 30.
Osteoarthritis (OA) is an age-related musculoskeletal disease that results in pain and functional disability. Stem cell therapy has been considered as a promising treatment for OA. In this study, the therapeutic action and potential mechanism of synovial mesenchymal stem cells (SMSCs)-derived exosomes (Exos) in OA cartilage damage were investigated. Cartilage cells were stimulated with IL-1β to establish an model of OA cartilage damage. Cartilage cell functions were detected by CCK-8, scratch assay, and flow cytometry, respectively. Inflammatory cytokine levels were assessed by ELISA. Target molecule levels were measured by qRT‒PCR and Western blotting. Exos-induced differential expression of miRNAs in cartilage cells were analyzed by microarray analysis. The interaction between miR-485-3p and neuropilin-1 (NRP1) was validated by dual luciferase reporter and RIP assays. We found that treatment with Exos promoted proliferation, migration, and ECM secretion, but restrained apoptosis and inflammation of IL-1β-exposed cartilage cells via up-regulation of miR-485-3p. Additionally, miR-485-3p directly targeted NRP1 to repress NRP1 expression, which subsequently caused inactivation of the PI3K/Akt pathway. The protective effect of Exos on cartilage damage was counteracted by NRP1 overexpression-mediated activation of the PI3K/Akt pathway. In conclusion, Exos delivered miR-485-3p to attenuate IL-1β-induced cartilage degradation by targeting NRP1 and succedent inactivation of the PI3K/Akt pathway. Our findings shed light on the novel protective mechanism of Exos in OA, which suggest that the restoration of miR-485-3p by Exos might be a novel approach for OA treatment.
骨关节炎（OA）是一种与年龄相关的肌肉骨骼疾病，会导致疼痛和功能障碍。干细胞疗法已被视为OA的一种有前景的治疗方法。在本研究中，研究了滑膜间充质干细胞（SMSCs）来源的外泌体（Exos）在OA软骨损伤中的治疗作用及潜在机制。用白细胞介素-1β（IL-1β）刺激软骨细胞以建立OA软骨损伤模型。分别通过CCK-8、划痕试验和流式细胞术检测软骨细胞功能。通过酶联免疫吸附测定（ELISA）评估炎性细胞因子水平。通过定量逆转录聚合酶链反应（qRT-PCR）和蛋白质免疫印迹法测量靶分子水平。通过基因芯片分析分析Exos诱导的软骨细胞中微小核糖核酸（miRNAs）的差异表达。通过双荧光素酶报告基因和RNA免疫沉淀（RIP）试验验证了miR-485-3p与神经纤毛蛋白-1（NRP1）之间的相互作用。我们发现，Exos处理通过上调miR-485-3p促进了IL-1β刺激的软骨细胞的增殖、迁移和细胞外基质（ECM）分泌，但抑制了其凋亡和炎症。此外，miR-485-3p直接靶向NRP1以抑制NRP1表达，随后导致磷脂酰肌醇-3激酶/蛋白激酶B（PI3K/Akt）通路失活。NRP1过表达介导的PI3K/Akt通路激活抵消了Exos对软骨损伤的保护作用。总之，Exos通过靶向NRP1及随后的PI3K/Akt通路失活来递送miR-485-3p，以减轻IL-1β诱导的软骨降解。我们的研究结果揭示了Exos在OA中的新型保护机制，这表明Exos恢复miR-485-3p可能是OA治疗的一种新方法。
