Zhujiang Newtown Dental Clinic, Guanghua School of Stomatology, Hospital of Stomatology, Institute of Stomatological Research, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-Sen University, No.49 Huaxia Road, Guangzhou, 510627, Guangdong, People's Republic of China.
Guanghua School of Stomatology, Hospital of Stomatology, Institute of Stomatological Research, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-Sen University, No.56 Lingyuan West Rd, Guangzhou, 510080, People's Republic of China.
Calcif Tissue Int. 2021 May;108(5):640-653. doi: 10.1007/s00223-020-00789-x. Epub 2021 Jan 12.
Human periodontal ligament stem cells (hPDLSCs) can undergo osteogenic differentiation under induction conditions. Cyclic tensile stress (CTS) can stimulate stem cell osteogenic differentiation. The present study explored the mechanism of CTS in hPDLSC osteogenic differentiation. The hPDLSCs of the 4th passage were selected. hPDLSCs were subjected to CTS with deformation of 10% elongation at 0.5 Hz for 1, 4, 8, 12 and 24 h. ALP activity and staining, ARS staining and detection of expressions of osteogenesis-related genes (RUNX2, OPN, Sp7 and OCN) were used to assess hPDLSC osteogenic differentiation ability. microRNA (miR)-129-5p and BMP2 expression and p-Smad1/5 level were detected under CTS stimulation. The binding relationship between miR-129-5p and BMP2 was predicted and verified. The osteogenic differentiation ability of CTS-treated hPDLSCs was evaluated after intervention of miR-129-5p and BMP2. CTS induced hPDLSC osteogenic differentiation, as manifested by increased ALP activities, osteogenesis-related gene expressions and mineralized nodules, together with positive ALP staining. CTS inhibited miR-129-5p expression, and promoted BMP2 expression and p-Smad1/5 level in hPDLSCs. miR-129-5p targeted BMP2. Overexpressed miR-129-5p or silenced BMP2 prevented hPDLSC osteogenic differentiation ability. We demonstrated that CTS inhibited miR-129-5p expression, and then activated the BMP2/Smad pathway, thereby showing stimulative effects on hPDLSC osteogenic differentiation.
人牙周韧带干细胞（hPDLSCs）在诱导条件下可向成骨细胞分化。循环张应变（CTS）可刺激干细胞向成骨细胞分化。本研究探讨了 CTS 对 hPDLSC 成骨分化的作用机制。选取第 4 代 hPDLSCs，对 hPDLSCs 施加 0.5Hz 频率下 10%伸长变形的 CTS，作用 1、4、8、12 和 24h。通过碱性磷酸酶（ALP）活性和染色、抗酒石酸酸性磷酸酶（ARS）染色以及检测成骨相关基因（RUNX2、OPN、Sp7 和 OCN）的表达，评估 hPDLSC 的成骨分化能力。在 CTS 刺激下检测微小 RNA（miR）-129-5p 和骨形态发生蛋白 2（BMP2）的表达及 p-Smad1/5 水平。预测并验证 miR-129-5p 与 BMP2 的结合关系。干预 miR-129-5p 和 BMP2 后，评估 CTS 处理的 hPDLSCs 的成骨分化能力。CTS 诱导 hPDLSC 成骨分化，表现为 ALP 活性、成骨相关基因表达和矿化结节增加，以及 ALP 染色阳性。CTS 抑制 miR-129-5p 的表达，并促进 hPDLSCs 中 BMP2 的表达和 p-Smad1/5 水平。miR-129-5p 靶向 BMP2。过表达 miR-129-5p 或沉默 BMP2 可阻止 hPDLSC 的成骨分化能力。我们证明 CTS 抑制 miR-129-5p 的表达，进而激活 BMP2/Smad 通路，从而对 hPDLSC 的成骨分化表现出促进作用。
