Liu Chao, Dong Jian Yong, Yue Lin Lin, Liu Shao Hua, Wan Yi, Liu Hong, Tan Wan Ye, Guo Qian Qian, Zhang Dong
Department of Oral and Maxillofacial Surgery and Institute of Dental Medicine, Qilu Hospital, Shandong University, Jinan, China.
School of Stomotology, Shandong University, Jinan, China.
PLoS One. 2017 Feb 9;12(2):e0171693. doi: 10.1371/journal.pone.0171693. eCollection 2017.
Endosseous titanium (Ti) implant failure due to poor biocompatibility of implant surface remains a major problem for osseointegration. Improving the topography of Ti surface may enhance osseointegration, however, the mechanism remains unknown. To investigate the effect of modified Ti surface on osteogenesis, we loaded rapamycin (RA) onto nano-hydroxyapatite (HAp) coated Ti surface which was acid-etched, alkali-heated and HAp coated sequentially. Sodium hyaluronate (SH) was employed as an intermediate layer for the load of RA, and a steady release rate of RA was maintained. Cell vitality of MC3T3-E1 was assessed by MTT. Osteogenesis of MC3T3-E1 on this modified Ti surface was evaluated by alkaline phosphatase (ALP) activity, mineralization and related osteogenesis genes osteocalcin (OCN), osteopontin (OPN), Collagen-I and Runx2. The result revealed that RA/SH-loaded nano-HAp Ti surface was innocent for cell vitality and even more beneficial for cell osteogenesis in vitro. Furthermore, osteogenesis of MC3T3-E1 showed significant association with the mammalian target of rapamycin (mTOR) phosphorylation by RA, which required further study about the mechanism. The approach to this modified Ti surface presented in this paper has high research value for the development of Ti-based implant.
由于种植体表面生物相容性差导致的骨内钛（Ti）种植体失败仍然是骨整合的一个主要问题。改善钛表面的形貌可能会增强骨整合，然而，其机制尚不清楚。为了研究改性钛表面对成骨的影响，我们将雷帕霉素（RA）负载到依次经过酸蚀、碱热和羟基磷灰石（HAp）涂层处理的纳米羟基磷灰石涂层钛表面。透明质酸钠（SH）用作负载RA的中间层，并维持RA的稳定释放速率。通过MTT评估MC3T3-E1细胞活力。通过碱性磷酸酶（ALP）活性、矿化以及相关成骨基因骨钙素（OCN）、骨桥蛋白（OPN）、I型胶原蛋白和Runx2评估MC3T3-E1在这种改性钛表面的成骨情况。结果表明，负载RA/SH的纳米HAp钛表面对细胞活力无害，甚至在体外更有利于细胞成骨。此外，MC3T3-E1的成骨与RA对哺乳动物雷帕霉素靶蛋白（mTOR）的磷酸化有显著关联，这需要进一步研究其机制。本文提出的这种改性钛表面的方法对钛基种植体的开发具有很高的研究价值。
