Objective

The aim of this study was to investigate the molecular mechanism of human bone marrow mesenchymal stem cells (hMSCs) secreting miR-26a exosomes on the function of skin fibroblasts.

Methods

Exosomes from hMSCs were extracted and identified by transmission electron microscopy, particle size was analyzed and protein markers were detected. Then, the exosomes were co-cultured with human skin fibroblasts (BJ). CCK-8, Annexin V/P and Transwell assays were used to detect the proliferation, apoptosis, and migration of BJ cells. In addition, the expressions of miR-26a, related proteins, and related inflammatory factors were detected by qRT-PCR, western blotting, and ELISA.

Results

Compared with the high glucose group, the proliferation rate, migration rate, and the expression of α-SMA, bcl-2, TLR4, NF-κB, TNF-α, IL-6, IL- and IL-1 were significantly decreased in the high glucose + MSC-Exo-miR-26a mimics group, while the apoptosis rate and the expression of miR-26a, cleaved-caspase 3, cleaved-caspase 9 and Bax were significantly increased. The results of the high glucose + MSC-Exo-miR-26a inhibitor group were the opposite.

Conclusion

These results suggest that hMSCs cells secreting miR-26a exosomes inhibited the proliferation, migration, and transdifferentiation of high glucose-induced BJ cells, and promoted cell apoptosis, which may be related to the TLR4/NF-κB signaling pathway.

中文翻译：

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骨髓间充质干细胞分泌miR-26a外泌体通过调节TLR4/NF-κB信号影响高糖诱导皮肤成纤维细胞功能的机制

客观的

本研究旨在探讨人骨髓间充质干细胞 (hMSCs) 分泌 miR-26a 外泌体对皮肤成纤维细胞功能的分子机制。

方法

通过透射电子显微镜提取和鉴定来自 hMSC 的外泌体，分析粒径并检测蛋白质标记物。然后，外泌体与人皮肤成纤维细胞（BJ）共培养。 CCK-8、Annexin V/P和Transwell实验用于检测BJ细胞的增殖、凋亡和迁移。此外，通过qRT-PCR、蛋白质印迹和ELISA检测miR-26a、相关蛋白和相关炎症因子的表达。

结果

与高糖组相比，细胞增殖率、迁移率和α-SMA、bcl-2、TLR4、NF-κB、TNF-α、IL-6、IL-和IL-1的表达均显着降低。高糖+MSC-Exo-miR-26a模拟物组细胞凋亡率和miR-26a、cleaved-caspase 3、cleaved-caspase 9和Bax的表达显着增加。高糖+MSC-Exo-miR-26a抑制剂组结果相反。

结论

这些结果表明，分泌miR-26a外泌体的hMSCs细胞抑制高糖诱导的BJ细胞增殖、迁移和转分化，促进细胞凋亡，这可能与TLR4/NF-κB信号通路有关。