Qi S, Wu Q, Ma J, Li J, Chen F, Xu Y, Pan Q, Wang R
Department of Stomatology, Shanghai Tenth People's Hospital, Tongji University, Shanghai, 200072, China.
Cell Prolif. 2015 Apr;48(2):221-30. doi: 10.1111/cpr.12171.
This study aimed to investigate effects of neurotrophin receptor-mediated melanoma antigen-encoding gene homology (NRAGE) on proliferation and odontoblastic differentiation of mouse dental pulp cells (mDPCs).
Mouse dental pulp cells were infected with recombinant lentivirus to stably knockdown expression of NRAGE, and biological effects of NRAGE on the cells were detected. Proliferation and odontoblastic differentiation of mDPCs were observed. Simultaneously, mRNA and protein levels of NRAGE and nuclear factor-κB (NF-κB) protein expression were detected. Immunofluorescence assay was used to detect expression and location of NRAGE and NF-κB.
NRAGE mRNA and protein levels reduced significantly after mDPC odontoblastic induction. Knockdown of NRAGE inhibited the proliferation of mDPCs. However, knockdown of NRAGE enhanced their odontoblastic differentiation with up-regulated ALPase activity. It also promoted mineral nodule formation as well as mRNA and protein expressions of ALP, DSPP and DMP1. Protein levels of NF-κB/p50 significantly increased, whereas NF-κB/p105 protein expression decreased in the mDPC/shNRG group. Immunofluorescence revealed that relocation of NF-κB was similar to that of NRAGE during odontoblastic induction, in which NF-κB translocated from the cytoplasm to the nucleus.
NRAGE is a potent regulator of proliferation and odontoblastic differentiation of mDPCs, which might be via the NF-κB signalling pathway.
本研究旨在探讨神经营养因子受体介导的黑色素瘤抗原编码基因同源物（NRAGE）对小鼠牙髓细胞（mDPCs）增殖和成牙本质细胞分化的影响。
用重组慢病毒感染小鼠牙髓细胞以稳定敲低NRAGE的表达，并检测NRAGE对细胞的生物学效应。观察mDPCs的增殖和成牙本质细胞分化情况。同时，检测NRAGE的mRNA和蛋白水平以及核因子-κB（NF-κB）蛋白表达。采用免疫荧光法检测NRAGE和NF-κB的表达及定位。
mDPCs成牙本质细胞诱导后，NRAGE的mRNA和蛋白水平显著降低。敲低NRAGE抑制了mDPCs的增殖。然而，敲低NRAGE增强了它们的成牙本质细胞分化，碱性磷酸酶（ALPase）活性上调。它还促进了矿化结节的形成以及ALP、牙本质涎磷蛋白（DSPP）和牙本质基质蛋白1（DMP1）的mRNA和蛋白表达。在mDPC/shNRG组中，NF-κB/p50的蛋白水平显著升高，而NF-κB/p105蛋白表达降低。免疫荧光显示，在成牙本质细胞诱导过程中，NF-κB的重新定位与NRAGE相似，即NF-κB从细胞质转移到细胞核。
NRAGE是mDPCs增殖和成牙本质细胞分化的有效调节因子，可能通过NF-κB信号通路发挥作用。
