State Key Laboratory for Environment-friendly Energy Materials, Southwest University of Science and Technology, Mianyang 621010, China.
National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China; Medprin Institute of Technology, Guangzhou 510663, China.
Mater Sci Eng C Mater Biol Appl. 2019 Dec;105:110065. doi: 10.1016/j.msec.2019.110065. Epub 2019 Aug 8.
In order to investigate the influence of Zn on the hydration reaction of calcium phosphate cement (CPC), the incompletely hydrated CPC tablets were kept soaking in varying zinc-containing tris-(hydroxymethyl)-aminomethane/hydrochloric acid (Zn-Tris-HCl) buffers. It was found that Zn could retard the CPC hydration, the inhibitory effect was in direct proportional to the Zn content in the Zn-Tris-HCl buffer, and overhigh concentration of Zn (≧800 μM) caused the CPC hydration products having different phase composition and surface morphology. Cell culture experimental results revealed the CPC tablets which were soaked in the Zn-Tris-HCl buffer containing relative low Zn content (≦320 μM) favored the mouse bone mesenchymal stem cells (mBMSCs) spreading. When Zn-doped CPC tablets released 10.91 to 27.15 μM of zinc ions into the cell culture medium, it greatly contributed to the improvement of the proliferation ability and the alkaline phosphatase (ALP) activity of the mBMSCs. In the same case, the expression of osteogenesis related genes such as collagen I and runt-related transcription factor 2 was remarkably up-regulated as well. However, the release of high concentration of Zn (128.58 μM) would significantly reduce the ALP activity of the mBMSCs. Therefore, Zn not only facilitates osteogenesis but also affects the CPC hydration behavior, and the CPC with suitable Zn dosage concentration has great potentials to be used for clinical bone repairing.
为了研究锌对磷酸钙水泥（CPC）水化反应的影响，将未完全水化的 CPC 片剂浸泡在不同含锌的三羟甲基氨基甲烷/盐酸（Zn-Tris-HCl）缓冲液中。结果发现，锌可以延缓 CPC 的水化，抑制作用与 Zn-Tris-HCl 缓冲液中的锌含量成正比，过高浓度的锌（≧800μM）会导致 CPC 水化产物具有不同的相组成和表面形貌。细胞培养实验结果表明，浸泡在 Zn-Tris-HCl 缓冲液中锌含量相对较低（≦320μM）的 CPC 片剂有利于小鼠骨髓间充质干细胞（mBMSCs）的铺展。当掺杂锌的 CPC 片剂向细胞培养液中释放 10.91 至 27.15μM 的锌离子时，极大地促进了 mBMSCs 的增殖能力和碱性磷酸酶（ALP）活性的提高。在相同情况下，骨形成相关基因如胶原 I 和 runt 相关转录因子 2 的表达也显著上调。然而，释放高浓度的锌（128.58μM）会显著降低 mBMSCs 的 ALP 活性。因此，锌不仅促进成骨，而且还影响 CPC 的水化行为，具有合适锌剂量浓度的 CPC 具有很大的临床骨修复潜力。
