Department of Endodontology and Operative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
Division of Endodontology, Kyushu University Hospital, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
Arch Oral Biol. 2017 Jun;78:135-143. doi: 10.1016/j.archoralbio.2017.02.018. Epub 2017 Feb 24.
The aim of this study was to investigate transforming growth factor-β-induced gene product-h3 (βig-h3) expression in dental pulp tissue and its effects on odontoblastic differentiation of dental pulp cells (DPCs).
A rat direct pulp capping model was prepared using perforated rat upper first molars capped with mineral trioxide aggregate cement. Human DPCs (HDPCs) were isolated from extracted teeth. βig-h3 expression in rat dental pulp tissue and HDPCs was assessed by immunostaining. Mineralization of HDPCs was assessed by Alizarin red-S staining. Odontoblast-related gene expression in HDPCs was analyzed by quantitative RT-PCR.
Expression of βig-h3 was detected in rat dental pulp tissue, and attenuated by direct pulp capping, while expression of interleukin-1β and tumor necrosis factor-α was increased in exposed pulp tissue. βig-h3 expression was also detected in HDPCs, with reduced expression during odontoblastic differentiation. The above cytokines reduced βig-h3 expression in HDPCs, and promoted their mineralization. Recombinant βig-h3 inhibited the expression of odontoblast-related genes and mineralization of HDPCs, while knockdown of βig-h3 gene expression promoted the expression of odontoblast-related genes in HDPCs.
The present findings suggest that βig-h3 in DPCs may be involved in reparative dentin formation and that its expression is likely to negatively regulate this process.
本研究旨在探讨转化生长因子-β诱导基因产物-h3（βig-h3）在牙髓组织中的表达及其对牙髓细胞（DPCs）成牙本质分化的影响。
采用在上颌第一磨牙穿孔后用三氧化矿物凝聚体水泥覆盖的方法制备大鼠直接牙髓盖髓模型。从拔除的牙齿中分离出人牙髓细胞（HDPCs）。通过免疫染色评估大鼠牙髓组织和 HDPCs 中βig-h3 的表达。通过茜素红 S 染色评估 HDPCs 的矿化情况。通过定量 RT-PCR 分析 HDPCs 中成牙本质相关基因的表达。
βig-h3 在大鼠牙髓组织中表达，直接盖髓后表达减弱，而暴露的牙髓组织中白细胞介素-1β和肿瘤坏死因子-α的表达增加。βig-h3 也在 HDPCs 中表达，在成牙本质分化过程中表达减少。上述细胞因子降低了 HDPCs 中βig-h3 的表达，并促进了其矿化。重组βig-h3 抑制 HDPCs 中成牙本质相关基因的表达和矿化，而βig-h3 基因表达的敲低则促进 HDPCs 中成牙本质相关基因的表达。
本研究结果表明，DPCs 中的βig-h3 可能参与修复性牙本质的形成，其表达可能负调控该过程。
