Shimazu A, Bachchu M A, Morishita M, Noshiro M, Kato Y, Iwamoto Y
Department of Preventive Dentistry, Hiroshima University School of Dentistry, Japan.
J Dent Res. 1999 Dec;78(12):1791-9. doi: 10.1177/00220345990780120501.
Syndecans are transmembrane heparan sulfate proteoglycans. They are known to interact with basic fibroblast growth factor (bFGF), and it has been suggested that they play important roles in the growth, morphology, and migration of a variety of cell types. We examined the expression of syndecans and fibroblast growth factor receptor type 1 (FGFR1) in periodontal ligament (PDL) cells, because these membrane proteins may play roles in the control of growth and differentiation during regeneration of PDL. Reverse-transcription/polymerase chain-reaction (RT-PCR) showed that PDL cells expressed syndecan-2 and -4 mRNAs. This was confirmed by sequence analysis of the PCR products. When PDL cells were maintained for 25 days, alkaline phosphatase (ALPase) activity gradually increased and reached a maximal level on day 20. Northern blotting analysis showed that PDL cells expressed 2.3-kb syndecan-2, 2.6-kb syndecan-4, and 2.8-kb FGFR1 mRNAs throughout the entire culture period, whereas no syndecan-1 mRNA was detectable by this method. Maximal levels of syndecan-2, -4, and FGFR1 mRNAs were observed on day 5. However, their levels were markedly decreased on days 20 and 25. Accordingly, the inhibitory effect of bFGF on ALPase activity was less on day 20 than on day 5. When PDL cells were pre-treated with heparitinase, a mitogenic response of PDL cells to bFGF was decreased. These observations indicate that PDL cells express syndecan-2, -4, and FGFR1 mRNAs, and that those levels are changed with the increase in ALPase activity in culture. The reductions in syndecan-2, -4, and FGFR1 levels may be involved in the control of growth and differentiation of PDL cells during development and regeneration.
Syndecans是跨膜硫酸乙酰肝素蛋白聚糖。已知它们能与碱性成纤维细胞生长因子（bFGF）相互作用，并且有人提出它们在多种细胞类型的生长、形态和迁移中发挥重要作用。我们检测了牙周膜（PDL）细胞中Syndecans和成纤维细胞生长因子受体1型（FGFR1）的表达，因为这些膜蛋白可能在PDL再生过程中的生长和分化控制中发挥作用。逆转录/聚合酶链反应（RT-PCR）显示PDL细胞表达Syndecan-2和-4 mRNA。通过PCR产物的序列分析证实了这一点。当PDL细胞培养25天时，碱性磷酸酶（ALPase）活性逐渐增加，并在第20天达到最高水平。Northern印迹分析表明，PDL细胞在整个培养期间都表达2.3 kb的Syndecan-2、2.6 kb的Syndecan-4和2.8 kb的FGFR1 mRNA，而用这种方法未检测到Syndecan-1 mRNA。在第5天观察到Syndecan-2、-4和FGFR1 mRNA的最高水平。然而，它们的水平在第20天和第25天明显下降。因此，bFGF对ALPase活性的抑制作用在第20天比第5天小。当PDL细胞用肝素酶预处理时，PDL细胞对bFGF的促有丝分裂反应降低。这些观察结果表明，PDL细胞表达Syndecan-2、-4和FGFR1 mRNA，并且这些水平随着培养中ALPase活性的增加而变化。Syndecan-2、-4和FGFR1水平的降低可能参与了PDL细胞在发育和再生过程中的生长和分化控制。
