Ke Z, Huang Z, He R, Zhang Q, Chen S, Cui Z K, Ding J
Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515 China.
Department of Pediatric Orthopedics, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China.
Nan Fang Yi Ke Da Xue Xue Bao. 2024 Jul 20;44(7):1227-1235. doi: 10.12122/j.issn.1673-4254.2024.07.02.
To investigate the role of high-mobility group AT-hook 2 (HMGA2) in osteogenic differentiation of adipose-derived mesenchymal stem cells (ADSCs) and the effect of knockdown for promoting bone defect repair.
Bioinformatics studies using the GEO database and Rstudio software identified HMGA2 as a key factor in adipogenic-osteogenic differentiation balance of ADSCs. The protein-protein interaction network of HMGA2 in osteogenic differentiation was mapped using String and visualized with Cytoscape to predict the downstream targets of HMGA2. Primary mouse ADSCs (mADSCs) were transfected with siRNA, and the changes in osteogenic differentiation of the cells were evaluated using alkaline phosphatase staining and Alizarin red S staining. The expressions of osteogenic markers Runt-related transcription factor 2 (RUNX2), osteopontin (OPN), and osteocalcein (OCN) in the transfected cells were detected using RT-qPCR and Western blotting. In a mouse model of critical-sized calvarial defects, mADSCs with knockdown were transplanted into the defect, and bone repair was evaluated 6 weeks later using micro-CT scanning and histological staining.
GEO database analysis showed that expression was upregulated during adipogenic differentiation of ADSCs. Protein-protein interaction network analysis suggested that the potential HMGA2 targets in osteogenic differentiation of ADSCs included SMAD7, CDH1, CDH2, SNAI1, SMAD9, IGF2BP3, and ALDH1A1. In mADSCs, knockdown significantly upregulated the expressions of RUNX2, OPN, and OCN and increased cellular alkaline phosphatase activity and calcium deposition. In a critical-sized calvarial defect model, transplantation of mADSCs with knockdown significantly promoted new bone formation.
HMGA2 is a crucial regulator of osteogenic differentiation in ADSCs, and knockdown significantly promotes osteogenic differentiation of ADSCs and accelerates ADSCs-mediated bone defect repair in mice.
探讨高迁移率族AT钩蛋白2（HMGA2）在脂肪来源间充质干细胞（ADSCs）成骨分化中的作用以及敲低HMGA2对促进骨缺损修复的影响。
利用GEO数据库和Rstudio软件进行生物信息学研究，确定HMGA2是ADSCs成脂-成骨分化平衡的关键因子。使用String绘制HMGA2在成骨分化中的蛋白质-蛋白质相互作用网络，并通过Cytoscape进行可视化，以预测HMGA2的下游靶点。用小干扰RNA（siRNA）转染原代小鼠ADSCs（mADSCs），通过碱性磷酸酶染色和茜素红S染色评估细胞成骨分化的变化。采用逆转录-定量聚合酶链反应（RT-qPCR）和蛋白质免疫印迹法检测转染细胞中成骨标志物Runx相关转录因子2（RUNX2）、骨桥蛋白（OPN）和骨钙素（OCN）的表达。在临界大小的颅骨缺损小鼠模型中，将敲低HMGA2的mADSCs移植到缺损处，6周后通过显微计算机断层扫描（micro-CT）和组织学染色评估骨修复情况。
GEO数据库分析显示，在ADSCs成脂分化过程中HMGA2表达上调。蛋白质-蛋白质相互作用网络分析表明，ADSCs成骨分化中潜在的HMGA2靶点包括SMAD7、CDH1、CDH2、SNAI1、SMAD9、IGF2BP3和ALDH1A1。在mADSCs中，敲低HMGA2显著上调RUNX2、OPN和OCN的表达，并增加细胞碱性磷酸酶活性和钙沉积。在临界大小的颅骨缺损模型中，移植敲低HMGA2的mADSCs显著促进了新骨形成。
HMGA2是ADSCs成骨分化的关键调节因子，敲低HMGA2可显著促进ADSCs的成骨分化，并加速ADSCs介导的小鼠骨缺损修复。
