Shiba H, Nakamura S, Shirakawa M, Nakanishi K, Okamoto H, Satakeda H, Noshiro M, Kamihagi K, Katayama M, Kato Y
Department of Endodontology and Periodontology, Hiroshima University School of Dentistry, Japan.
Dev Biol. 1995 Aug;170(2):457-66. doi: 10.1006/dbio.1995.1229.
Basic fibroblast growth factor (bFGF) may be involved in the development and repair of dentine and pulp because bFGF, its related peptides, and FGF receptors are expressed in dental mesenchymal cells. In this study, we examined the effects of bFGF on DNA synthesis, osteonectin/SPARC levels, alkaline phosphatase (ALPase) activity, their mRNA levels, and calcium levels in cultures of human pulp cells. Pulp cells were isolated from three healthy upper wisdom teeth of three patients and maintained separately. These cells produced SPARC, ALPase, and calcified nodules and there was a close correlation between the SPARC-synthetic activity of the cell lines and their levels of ALPase and calcification. The levels of SPARC, ALPase and calcium deposits in the three pulp cell cultures were 10-250 times those of human foreskin fibroblasts. Western blots showed that the pulp cells produced 38-kDa SPARC. Northern blots showed that the pulp cells expressed flg (FGF receptor type 1) transcripts throughout all culture stages, irrespective of the presence or absence of bFGF. The addition of bFGF to the pulp cultures suppressed the increases in ALPase activity, SPARC synthesis, and their mRNA levels, although it increased the incorporation of [3H]thymidine into DNA > 10-fold. The effects of bFGF on ALPase activity and SPARC synthesis were reversible. Furthermore, bFGF abolished the calcification of the extracellular matrix; the calcium content of bFGF-free cultures. These findings suggest that bFGF is a potent mitogen for human pulp cells and that it inhibits the expression of the odontoblast phenotype by the cells at least partly at pretranslational levels.
碱性成纤维细胞生长因子（bFGF）可能参与牙本质和牙髓的发育与修复，因为bFGF、其相关肽以及FGF受体在牙间充质细胞中表达。在本研究中，我们检测了bFGF对人牙髓细胞培养物中DNA合成、骨连接蛋白/富含半胱氨酸的酸性分泌蛋白（SPARC）水平、碱性磷酸酶（ALPase）活性、它们的mRNA水平以及钙水平的影响。从三名患者的三颗健康上颌智齿中分离出牙髓细胞并分别进行培养。这些细胞产生SPARC、ALPase和钙化结节，并且细胞系的SPARC合成活性与其ALPase水平和钙化之间存在密切相关性。三种牙髓细胞培养物中SPARC、ALPase和钙沉积的水平是人包皮成纤维细胞的10 - 250倍。蛋白质免疫印迹显示牙髓细胞产生38 kDa的SPARC。Northern印迹显示牙髓细胞在所有培养阶段均表达flg（1型FGF受体）转录本，无论是否存在bFGF。向牙髓培养物中添加bFGF可抑制ALPase活性、SPARC合成及其mRNA水平的增加，尽管它使[3H]胸腺嘧啶核苷掺入DNA的量增加了10倍以上。bFGF对ALPase活性和SPARC合成的影响是可逆的。此外，bFGF消除了细胞外基质的钙化；无bFGF培养物的钙含量。这些发现表明bFGF是一种有效的人牙髓细胞促有丝分裂原，并且它至少部分在翻译前水平抑制细胞的成牙本质细胞表型的表达。
