Department of Endodontics and Operative Dentistry, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, Shanghai, China.
National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology &, Shanghai Research Institute of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Oral Dis. 2023 Jul;29(5):2107-2116. doi: 10.1111/odi.14195. Epub 2022 Apr 19.
Human dental pulp stem cells (hDPSCs) constitute a promising source of stem cells in tissue engineering. However, the molecular mechanism of differentiation in hDPSCs remains largely unclear. MicroRNAs (miRNAs) play crucial roles in lineage-specific differentiation of stem cells. The present study investigated the function of miRNA-342-5p in the odonto/osteogenic differentiation of hDPSCs.
The miRNA array profiling and quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) revealed the expression of miR-342-5p during odonto/osteogenic differentiation of hDPSCs. hDPSCs were treated with miR-342-5p mimic and inhibitor to investigate the regulatory roles of miR-342-5p in the differentiation of hDPSCs. Moreover, miR-342-5p inhibitor and small interference RNA (siRNA) targeting Wnt7b were applied to explore the regulatory mechanism of miR-342-5p.
Downregulated miR-342-5p was observed during odonto/osteogenic differentiation of hDPSCs. The overexpression of miR-342-5p inhibited the odonto/osteogenic potential of DPSCs, as indicated by low levels of alkaline phosphatase activity, calcium deposition formation, and odonto/osteogenic differentiation markers, whereas silencing of miR-342-5p exhibited the opposite effect. When co-treated with siRNA targeting Wnt7b and miR-342-5p inhibitor in hDPSCs, the odonto/osteogenic potential and activation of Wnt7b/β-catenin pathway were attenuated.
This study showed that miR-342-5p inhibits the odonto/osteogenic differentiation of hDPSCs by interfering with Wnt/β-catenin signaling via targeting Wnt7b.
人牙髓干细胞（hDPSCs）是组织工程中一种有前途的干细胞来源。然而，hDPSCs 分化的分子机制在很大程度上仍不清楚。微小 RNA（miRNA）在干细胞谱系特异性分化中发挥着关键作用。本研究探讨了 miRNA-342-5p 在 hDPSCs 牙向/成骨分化中的作用。
miRNA 芯片分析和实时定量逆转录聚合酶链反应（qRT-PCR）显示 miR-342-5p 在 hDPSCs 牙向/成骨分化过程中的表达。用 miR-342-5p 模拟物和抑制剂处理 hDPSCs，以研究 miR-342-5p 对 hDPSCs 分化的调节作用。此外，还应用 miR-342-5p 抑制剂和针对 Wnt7b 的小干扰 RNA（siRNA）来探讨 miR-342-5p 的调节机制。
在 hDPSCs 的牙向/成骨分化过程中观察到下调的 miR-342-5p。miR-342-5p 的过表达抑制了 DPSCs 的牙向/成骨潜能，表现为碱性磷酸酶活性、钙沉积形成和牙向/成骨分化标志物水平降低，而 miR-342-5p 的沉默则表现出相反的效果。当在 hDPSCs 中共同用 siRNA 靶向 Wnt7b 和 miR-342-5p 抑制剂处理时，牙向/成骨潜能和 Wnt7b/β-catenin 通路的激活受到抑制。
本研究表明，miR-342-5p 通过靶向 Wnt7b 干扰 Wnt/β-catenin 信号通路，抑制 hDPSCs 的牙向/成骨分化。
