Department of Orthopedics, the Fourth Medical Centre, Chinese PLA General Hospital, Beijing, 100048, China.
School of Fundamental Sciences, China Medical University, Shenyang 110122, China.
ACS Biomater Sci Eng. 2020 Oct 12;6(10):5785-5796. doi: 10.1021/acsbiomaterials.0c00852. Epub 2020 Sep 16.
Nerves spread throughout human bone minerals and play an important role in regulating osteogenic homeostasis. However, whether the distributive nerves can sense bone minerals and the role of bone minerals in nerve outgrowth are still unclear. We hypothesized that a natural magnesium-containing bone mineral, whitlockite (WH), the second most abundant bone mineral in the human body, could simultaneously promote both osteogenic and neural activities. To verify the hypothesis, both WH and hydroxyapatite (HAP) nanoparticles were synthesized, and their characterization was completed by Fourier-transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The effect of WH on neural differentiation of mesenchymal stem cells (MSCs) and neural progenitor cells (NPCs) in 2D and 3D culture was examined by immunostaining and quantitative real-time polymerase chain reaction (qRT-PCR). The secretion of calcitonin gene-related polypeptide (CGRP) was examined by enzyme-linked immunosorbent assay (ELISA). The neural and osteogenic differentiation in a preosteoblasts and NPCs coculture system was examined by immunostaining and qRT-PCR. The results showed that WH promotes the gene and protein expression of neuronal specific marker (MAP-2 and βIII-tubulin) in 2D and 3D culture systems. In addition, the neurite length in the WH group was significantly longer than in other groups. Furthermore, both neural differentiation and osteogenic differentiation were simultaneously enhanced in the WH group in the coculture system. Thus, this study demonstrated the simultaneous stimulatory effect of WH bone mineral on neural and osteogenic activities, which provided WH as a valuable material for bone regeneration.
神经分布于人体骨骼矿物质中，在调节成骨内稳态方面发挥着重要作用。然而，分布的神经是否可以感知骨骼矿物质，以及骨骼矿物质在神经生长中的作用尚不清楚。我们假设一种天然含镁的骨骼矿物质——磷灰石（WH），它是人体中第二丰富的骨骼矿物质，能够同时促进成骨和神经活性。为了验证这一假设，我们合成了 WH 和羟基磷灰石（HAP）纳米颗粒，并通过傅里叶变换红外光谱（FT-IR）和 X 射线衍射（XRD）对其进行了表征。通过免疫染色和实时定量聚合酶链反应（qRT-PCR），研究了 WH 对间充质干细胞（MSCs）和神经祖细胞（NPCs）在 2D 和 3D 培养中的神经分化的影响。通过酶联免疫吸附测定（ELISA）检测降钙素基因相关肽（CGRP）的分泌。通过免疫染色和 qRT-PCR 检测成骨前体细胞和 NPCs 共培养体系中的神经和成骨分化。结果表明，WH 促进了 2D 和 3D 培养体系中神经元特异性标志物（MAP-2 和 βIII-微管蛋白）的基因和蛋白表达。此外，WH 组的神经突长度明显长于其他组。此外，在共培养体系中，WH 组的神经分化和成骨分化同时增强。因此，本研究证明了 WH 骨骼矿物质对神经和成骨活性的同时刺激作用，为 WH 作为骨再生的有价值材料提供了依据。
