Department of Stomatology, Central Hospital of Xuzhou, the Xuzhou Clinical College of Xuzhou Medical University, Xuzhou, Jiangsu Province, PR China.
These authors contributed equally to this article.
Cell Transplant. 2020 Jan-Dec;29:963689720934418. doi: 10.1177/0963689720934418.
In this study, we assessed the ability of miR-26b-5p to regulate T cell factor 4 (TCF-4) expression and thereby control human adipose-derived mesenchymal stem cell (hADMSC) adipogenic differentiation. Adipogenic medium was used to induce hADMSC differentiation over a 6-d period. The ability of miR-26b-5p to interact with the TCF-4 mRNA was confirmed through both predictive bioinformatics analyses and luciferase reporter assays. Immunofluorescent staining was used to visualize the impact of miR-26b-5p inhibition or overexpression on TCF-4 and β-catenin levels in hADMSCs. Further functional analyses were conducted by transfecting these cells with siRNAs specific for TCF-4 and β-catenin. Adipogenic marker and Wnt/β-catenin pathway gene expression levels were assessed via real-time polymerase chain reaction and western blotting. β-catenin localization was assessed via immunofluorescent staining. As expected, our adipogenic media induced the adipocytic differentiation of hADMSCs. In addition, we confirmed that TCF-4 is an miR-26b-5p target gene in these cells, and that protein levels of both TCF-4 and β-catenin were reduced when these cells were transfected with miR-26b-5p mimics. Overexpression of this microRNA also enhanced hADMSC adipogenesis, whereas TCF-4 and β-catenin overexpression inhibited this process. The enhanced hADMSC adipogenic differentiation that was observed following TCF-4 or β-catenin knockdown was partially reversed when miR-26b-5p expression was inhibited. We found that miR-26b-5p serves as a direct negative regulator of TCF-4 expression within hADMSCs, leading to inactivation of the Wnt/β-catenin pathway and thereby promoting the adipogenic differentiation of these cells .
在这项研究中,我们评估了 miR-26b-5p 调控 T 细胞因子 4 (TCF-4) 表达的能力,从而控制人脂肪间充质干细胞 (hADMSC) 的成脂分化。用成脂培养基诱导 hADMSC 在 6 天内分化。通过预测生物信息学分析和荧光素酶报告基因实验证实了 miR-26b-5p 与 TCF-4 mRNA 相互作用的能力。免疫荧光染色用于可视化 miR-26b-5p 抑制或过表达对 hADMSC 中 TCF-4 和 β-连环蛋白水平的影响。通过转染针对 TCF-4 和 β-连环蛋白的特异性 siRNA 对这些细胞进行进一步的功能分析。通过实时聚合酶链反应和 Western blot 评估成脂标志物和 Wnt/β-连环蛋白通路基因的表达水平。通过免疫荧光染色评估 β-连环蛋白的定位。正如预期的那样,我们的成脂培养基诱导 hADMSC 向脂肪细胞分化。此外,我们证实 TCF-4 是这些细胞中 miR-26b-5p 的靶基因,并且当这些细胞转染 miR-26b-5p 模拟物时,TCF-4 和 β-连环蛋白的蛋白水平降低。这种微 RNA 的过表达也增强了 hADMSC 的成脂分化,而 TCF-4 和 β-连环蛋白的过表达则抑制了这一过程。当抑制 miR-26b-5p 的表达时,观察到 TCF-4 或 β-连环蛋白敲低后 hADMSC 成脂分化增强的部分逆转。我们发现 miR-26b-5p 作为 hADMSC 中 TCF-4 表达的直接负调节剂,导致 Wnt/β-连环蛋白通路失活,从而促进这些细胞的成脂分化。