Luo Zhirong, Kohli Meetu R, Yu Qing, Kim Syngcuk, Qu Tiejun, He Wen-xi
Department of Operative Dentistry and Endodontics, Fourth Military Medical University, Xian, China.
Department of Endodontics, University of Pennsylvania, Philadelphia, Pennsylvania.
J Endod. 2014 Jul;40(7):937-42. doi: 10.1016/j.joen.2013.11.022. Epub 2014 Jan 7.
Biodentine (Septodont, Saint-Maur-des-Fossès, France), a new tricalcium silicate cement formulation, has been introduced as a bioactive dentine substitute to be used in direct contact with pulp tissue. The aim of this study was to investigate the response of human dental pulp stem cells (hDPSCs) to the material and whether mitogen-activated protein kinase (MAPK), nuclear factor-kappa B (NF-κB), and calcium-/calmodulin-dependent protein kinase II (CaMKII) signal pathways played a regulatory role in Biodentine-induced odontoblast differentiation.
hDPCs obtained from impacted third molars were incubated with Biodentine. Odontoblastic differentiation was evaluated by alkaline phosphatase activity, alizarin red staining, and quantitative real-time reverse-transcriptase polymerase chain reaction for the analysis of messenger RNA expression of the following differentiation gene markers: osteocalcin (OCN), dentin sialophosprotein (DSPP), dentin matrix protein 1 (DMP1), and bone sialoprotein (BSP). Cell cultures in the presence of Biodentine were exposed to specific inhibitors of MAPK (U0126, SB203580, and SP600125), NF-κB (pyrrolidine dithiocarbamate), and CaMKII (KN-93) pathways to evaluate the regulatory effect on the expression of these markers and mineralization assay.
Biodentine significantly increased alkaline phosphatase activity and mineralized nodule formation and the expression of OCN, DSPP, DMP1, and BSP. The MAPK inhibitor for extracellular signal-regulated kinase 1/2 (U0126) and Jun N-terminal kinase (SP600125) significantly decreased the Biodentine-induced mineralized differentiation of hDPSCs and OCN, DSPP, DMP1, and BSP messenger RNA expression, whereas p38 MAPK inhibitors (SB203580) had no effect. The CaMKII inhibitor KN-93 significantly attenuated and the NF-κB inhibitor pyrrolidine dithiocarbamate further enhanced the up-regulation of Biodentine-induced gene expression and mineralization.
Biodentine is a bioactive and biocompatible material capable of inducing odontoblast differentiation of hDPSCs. Our results indicate that this induction is regulated via MAPK and CaMKII pathways.
生物活性牙本质（法国圣莫尔-德福尔塞的Septodont公司产品）是一种新型的硅酸三钙水门汀配方，已作为一种生物活性牙本质替代物引入，可直接与牙髓组织接触使用。本研究的目的是调查人牙髓干细胞（hDPSCs）对该材料的反应，以及丝裂原活化蛋白激酶（MAPK）、核因子-κB（NF-κB）和钙/钙调蛋白依赖性蛋白激酶II（CaMKII）信号通路在生物活性牙本质诱导成牙本质细胞分化过程中是否发挥调节作用。
将从阻生第三磨牙获取的hDPCs与生物活性牙本质一起培养。通过碱性磷酸酶活性、茜素红染色以及定量实时逆转录聚合酶链反应来评估成牙本质细胞分化，以分析以下分化基因标志物的信使核糖核酸表达：骨钙素（OCN）、牙本质涎磷蛋白（DSPP）、牙本质基质蛋白1（DMP1）和骨涎蛋白（BSP）。在存在生物活性牙本质的细胞培养物中加入MAPK（U0126、SB203580和SP600125）、NF-κB（吡咯烷二硫代氨基甲酸盐）和CaMKII（KN-93）信号通路的特异性抑制剂，以评估其对这些标志物表达和矿化测定的调节作用。
生物活性牙本质显著提高了碱性磷酸酶活性、矿化结节形成以及OCN、DSPP、DMP1和BSP的表达。细胞外信号调节激酶1/2（U0126）和Jun氨基末端激酶（SP600125）的MAPK抑制剂显著降低了生物活性牙本质诱导的hDPSCs矿化分化以及OCN、DSPP、DMP1和BSP信使核糖核酸表达，而p38 MAPK抑制剂（SB203580）则没有作用。CaMKII抑制剂KN-93显著减弱，NF-κB抑制剂吡咯烷二硫代氨基甲酸盐进一步增强了生物活性牙本质诱导的基因表达上调和矿化。
生物活性牙本质是一种能够诱导hDPSCs成牙本质细胞分化的生物活性和生物相容性材料。我们的结果表明，这种诱导是通过MAPK和CaMKII信号通路调节的。
