Regulation of ALP activity by TNF-α on human dental pulp
Regulation of ALP activity by TNF-α on human dental pulp
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DOI：
10.1016/j.joen.2005.12.007
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发表时间：
2006-06-01
影响因子：
4.2
通讯作者：
Matsushima, K
中科院分区：
文献类型：
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作者：
Okabe, T;Matsushima, K
本研究通过检测肿瘤坏死因子-α对人牙髓(HDP)细胞骨形态发生蛋白-2(BMP-2)及其信号转导通路Smads表达和碱性磷酸酶(ALP)活性的影响，探讨其在牙本质形成中的作用机制。在肿瘤坏死因子-α刺激下，HDP细胞BMP-2的RT-PCR产物数量增加。而与肿瘤坏死因子-α共同孵育的细胞，其碱性磷酸酶活性无明显升高。另一方面，吡咯烷二硫代氨基甲酸铵(PDTC、核因子-kappaB抑制剂)组及联合补充肿瘤坏死因子-α和PDTC组的HDP细胞ALP活性显著升高。此外，我们通过RT-PCR和Western印迹分析检测了肿瘤坏死因子-α和PDTC对Smad7表达的影响。HDP细胞中Smad7的表达在肿瘤坏死因子-α作用下表达增加，而在PDTC作用下表达降低。这些结果提示，核因子-kappaB和Smad7在肿瘤坏死因子-α下调HDP细胞ALP活性中起重要作用。
In this study, we examined the effects of TNF-alpha on Bone morphogenetic protein (BMP-2), Smads (which play intracellular signaling of BMPs) expression and alkaline phosphatase (ALP) activity of human dental pulp (HDP) cells to clarify the mechanism of tertiary dentin formation. The quantity of RT-PCR product for BMP-2 from the HDP cells stimulated by TNF-alpha is increased. However, ALP activity was not increased on the cells incubated with TNF-alpha. On the other hand, ALP activity was significantly increased on HDP cells treated with Ammonium Pyrrolidinedithiocarbamate (PDTC, NF- kappa B inhibitor) groups and combined supplementation of TNF-alpha and PDTC groups. Furthermore, we examined the effect of TNF-alpha and PDTC on Smad7 expression using RT-PCR and western blot analysis. Smad7 expression in HDP cells was increased by TNF-alpha, but decreased by PDTC treatment. These results suggest that NF- kappa B and Smad7 play an important role in the down regulation of ALP activity by TNF-alpha on HDP cells.