School of Stomatology, Shandong University, Jinan, Shandong 250012, P.R. China.
Int J Mol Med. 2019 Jan;43(1):167-176. doi: 10.3892/ijmm.2018.3947. Epub 2018 Oct 22.
1α, 25‑dihydroxyvitamin D3 (1,25‑D3), an active vitamin D metabolite, is a well‑known regulator of osteogenic differentiation. However, how 1,25‑D3 regulates osteogenic differentiation in human periodontal ligament stem cells (hPDLSCs) remains to be fully elucidated. The present study aimed to clarify this issue through well‑controlled in vitro experiments. After hPDLSCs were treated with 1,25‑D3, immunofluorescence and western blotting were used to detect the expression of vitamin D receptor; Cell Counting Kit‑8 and western blotting were used to assay the cell proliferation ability. Alkaline phosphatase staining, Alizarin Red staining and western blotting were used to detect the osteogenic differentiation. It was found that treating hPDLSCs with 1,25‑D3: i) Inhibited cell proliferation; ii) promoted osteogenic differentiation; iii) upregulated the expression of transcriptional coactivator with PDZ‑binding motif (TAZ), an important downstream effector of Hippo signaling that has been demonstrated to be involved in the osteogenic differentiation of stem/progenitor cells; and iv) that co‑treatment of TAZ‑overexpressing hPDLSCs with 1,25‑D3 synergistically stimulated the expression of osteogenic markers. These results suggested that the induction of osteogenic differentiation promoted by 1,25‑D3 in hPDLSCs involves, at least in part, the action of TAZ.
1α, 25-二羟维生素 D3（1,25-D3）是一种活性维生素 D 代谢物，是众所周知的成骨分化调节剂。然而，1,25-D3 如何调节人牙周膜干细胞（hPDLSCs）的成骨分化仍有待充分阐明。本研究旨在通过严格的体外实验来阐明这一问题。用 1,25-D3 处理 hPDLSCs 后，通过免疫荧光和 Western blot 检测维生素 D 受体的表达；通过细胞计数试剂盒-8 和 Western blot 检测细胞增殖能力。碱性磷酸酶染色、茜素红染色和 Western blot 用于检测成骨分化。结果发现，用 1,25-D3 处理 hPDLSCs：i）抑制细胞增殖；ii）促进成骨分化；iii）上调 Hippo 信号下游重要效应物 PDZ 结合基序转录共激活因子（TAZ）的表达，TAZ 已被证明参与干细胞/祖细胞的成骨分化；iv）与 1,25-D3 共处理过表达 TAZ 的 hPDLSCs 协同刺激成骨标志物的表达。这些结果表明，1,25-D3 诱导 hPDLSCs 成骨分化至少部分涉及 TAZ 的作用。
