The role of growth factors on wound healing of maxillofacial bone

机械应力影响骨创面愈合的分子基础尚未得到很好的研究。局部产生的自分泌或旁分泌因子调节伤口愈合过程。碱性成纤维细胞生长因子（bFGF）在这一过程中具有重要作用。我们在这里展示了bFGF的新发现。已知成纤维细胞生长因子-2 （FGF-2）间接刺激骨形成和骨吸收。我们研究了其对成熟破骨细胞的直接作用。在分离的兔破骨细胞培养中，FGF-2 （10-11M）表现出最大的刺激（1.9倍），而在骨细胞混合培养中，FGF-2 （10-9M）表现出7.5倍的刺激。FGF-2上调p42/p44丝裂原活化蛋白（MAP）激酶等细胞蛋白磷酸化水平，增加FGF受体-1激酶活性。这些结果表明，FGF-2通过激活FGF受体-1和p42/p44 MAP激酶直接作用于成熟破骨细胞，在生理或病理浓度下刺激骨吸收。

Molecular basis of wound healing of bone affected by mechanical stress has not been studied well. Locally produced autocrine or paracrine factors regulate the wound healing process. Basic fibroblast growth factor (bFGF) has the potent effects on this process. We have shown here the new findings of bFGF.Fibroblast growth factor-2 (FGF-2) is known to stimulate bone formation and resorption indirectly. We investigated the direct action of on mature osteoclasts. FGF-2 (10-11M) exhibited maximum stimulation (1.9-fold) of pit formation in isolated rabbit osteoclast cultures, whereas in mixed cultures of bone cells, FGF-2 (10-9M) showed the 7.5-fold stimulation. FGF-2 up-regulated the phosphorylation of cellular proteins including p42/p44 mitogen-activated protein (MAP) kinase, and increased the kinase-activity of FGF receptor-1. These results suggest that FGF-2 acts directly on mature osteoclasts through activation of FGF receptor-1 and p42/p44 MAP kinase, causing the stimulation of bone resorption at physiological or pathological concentrations.