Department of Orthopedics, Shanghai Fifth People's Hospital, Fudan University, 200240 Shanghai, China.
Front Biosci (Landmark Ed). 2024 Aug 9;29(8):278. doi: 10.31083/j.fbl2908278.
Bone tissue engineering offers a new approach for the treatment of bone defects, with angiogenesis being critical to the survival and development of tissue-engineered bone. Mineralized osteoblasts (MOBs) have been reported to promote vascular formation by endothelial cells (ECs) through the secretion of exosomes containing a variety of angiogenic factors. The aim of the present study was to investigate the effect of miR-423-5p contained within exosomes derived from MOBs (MOB-Exos) on EC angiogenesis.
The Cell Counting Kit-8 (CCK-8), scratch wound healing, Transwell migration, and tube formation assays were conducted to assess the effects of MOB-Exos on EC proliferation, migration, and tubule-forming capabilities. The miR-423-5p level in MOB-Exos was quantified using quantitative polymerase chain reaction (qPCR). Co-culture experiments were used to study the exosomal transport of miR-423-5p and its angiogenic effects. High-throughput sequencing was used to identify differentially expressed genes, and a dual luciferase reporter assay to determine whether was a direct target gene for miR-423-5p. Furthermore, the effect of MOB-Exos-derived miR-423-5p on angiogenesis was evaluated using a subcutaneous xenograft model.
MOB-Exos significantly promoted the proliferation, migration, and tubule formation of ECs. A high level of miR-423-5p was found in MOB-Exos and promoted the angiogenesis of ECs. The gene was significantly downregulated in ECs upon miR-423-5p mimic transfection. Dual luciferase reporter assay confirmed the direct binding of miR-423-5p to the gene. miR-423-5p derived from MOB-Exos upregulated expression of the vascular markers CD31 and vascular endothelial growth factor (VEGF) , thus underscoring its angiogenic potential.
This study found that miR-423-5p derived from MOB-Exos could potentially enhance EC angiogenesis via the regulation of CXCL10. Therefore, exosomes are promising therapeutic candidates for clinical bone defects.
骨组织工程为骨缺损的治疗提供了一种新方法，血管生成对于组织工程骨的存活和发展至关重要。已经有报道称，矿化成骨细胞（MOBs）通过分泌含有多种血管生成因子的外泌体来促进内皮细胞（ECs）的血管形成。本研究旨在探讨源自 MOB 的外泌体（MOB-Exos）中包含的 miR-423-5p 对 EC 血管生成的影响。
采用细胞计数试剂盒-8（CCK-8）、划痕愈合、Transwell 迁移和管形成实验评估 MOB-Exos 对 EC 增殖、迁移和管状形成能力的影响。采用定量聚合酶链反应（qPCR）定量检测 MOB-Exos 中的 miR-423-5p 水平。共培养实验用于研究外泌体中 miR-423-5p 的转运及其血管生成作用。高通量测序用于鉴定差异表达基因，双荧光素酶报告基因实验用于确定是否是 miR-423-5p 的直接靶基因。此外，采用皮下异种移植模型评估 MOB-Exos 衍生的 miR-423-5p 对血管生成的影响。
MOB-Exos 显著促进 EC 的增殖、迁移和管状形成。MOB-Exos 中存在高水平的 miR-423-5p，并促进 EC 的血管生成。miR-423-5p 模拟物转染后，ECs 中基因表达显著下调。双荧光素酶报告基因实验证实 miR-423-5p 与基因的直接结合。MOB-Exos 衍生的 miR-423-5p 上调了血管标记物 CD31 和血管内皮生长因子（VEGF）的表达，从而强调了其促血管生成作用。
本研究发现，MOB-Exos 衍生的 miR-423-5p 可能通过调节 CXCL10 增强 EC 血管生成。因此，外泌体是治疗临床骨缺损有前途的候选药物。
