Rousseau Marthe, Boulzaguet Hélène, Biagianti Julie, Duplat Denis, Milet Christian, Lopez Evelyne, Bédouet Laurent
Département des Milieux et Peuplements Aquatiques, UMR 5178, CNRS-MNHN Biologie des Organismes Marins et Ecosystèmes, ERT Valorisation de Molécules Bioactives d'Origine Marine, Paris, France.
J Biomed Mater Res A. 2008 May;85(2):487-97. doi: 10.1002/jbm.a.31553.
The nacre layer from the pearl oyster shell is considered as a promising osteoinductive biomaterial. Nacre contains one or more signal molecules capable of stimulating bone formation. The identity and the mode of action of these molecules on the osteoblast differentiation were analyzed. Water-soluble molecules from nacre were fractionated according to dialysis, solvent extraction, and reversed-phase HPLC. The activity of a fraction composed of low molecular weight molecules in the mineralization of the MC3T3-E1 extracellular matrix was investigated. Mineralization of the preosteoblast cells was monitored according to alizarin red staining, Raman spectroscopy, scanning electron microscopy, and quantitative RT-PCR. Molecules isolated from nacre, ranging from 50 to 235 Da, induced a red alizarin staining of the preosteoblasts extracellular matrix after 16 days of culture. Raman spectroscopy demonstrated the presence of hydroxyapatite (HA) in samples treated with these molecules. Scanning electron microscopy pictures showed at the surface of the treated cells the occurrence of clusters of spherical particles resembling to HA. The treatment of cells with nacre molecules accelerated expression of collagen I and increased the mRNA expression of Runx2 and osteopontin. This study indicated that the nacre molecules efficient in bone cell differentiation are certainly different from proteins, and could be useful for in vivo bone repair.
珍珠贝贝壳的珍珠层被认为是一种很有前景的骨诱导生物材料。珍珠层含有一种或多种能够刺激骨形成的信号分子。对这些分子在成骨细胞分化中的身份和作用方式进行了分析。根据透析、溶剂萃取和反相高效液相色谱法对珍珠层中的水溶性分子进行了分级分离。研究了由低分子量分子组成的一个级分在MC3T3-E1细胞外基质矿化中的活性。根据茜素红染色、拉曼光谱、扫描电子显微镜和定量逆转录-聚合酶链反应监测前成骨细胞的矿化情况。从珍珠层中分离出的分子量在50至235 Da之间的分子，在培养16天后诱导前成骨细胞外基质出现茜素红染色。拉曼光谱证明在用这些分子处理的样品中存在羟基磷灰石（HA）。扫描电子显微镜照片显示，在处理过的细胞表面出现了类似HA的球形颗粒簇。用珍珠层分子处理细胞可加速I型胶原蛋白的表达，并增加Runx2和骨桥蛋白的mRNA表达。这项研究表明，在骨细胞分化中有效的珍珠层分子肯定不同于蛋白质，并且可能对体内骨修复有用。
