Disease-Associated Extracellular Matrix Suppresses Osteoblastic Differentiation of Human Periodontal Ligament Cells Via MMP-1
Disease-Associated Extracellular Matrix Suppresses Osteoblastic Differentiation of Human Periodontal Ligament Cells Via MMP-1
复制标题
DOI：
10.1007/s00223-009-9321-z
复制
发表时间：
2010-02-01
影响因子：
4.2
通讯作者：
Kapila, Sunil
中科院分区：
文献类型：
--
作者：
Joseph, Jeena;Kapila, Yvonne L.;Kapila, Sunil
在慢性炎症性疾病，包括牙周病和关节炎中发现的纤连蛋白（FN）片段可能部分通过诱导基质金属蛋白酶（MMPs）导致组织破坏。我们以前表明，120 kDa的FN片段含有中央细胞结合域（120 FN）剂量依赖性诱导MMP-1（胶原酶-1）在人牙周膜（PDL）细胞，而完整的FN没有引起这种反应。最近，我们发现MMP-1表达的增加伴随着PDL细胞中成骨细胞表型的减少。我们推测120 FN通过诱导MMP-1抑制PDL细胞的成骨分化。使用Western印迹、qRT-PCR、胶原降解和碱性磷酸酶（AP）活性测定，在培养的PDL细胞中评估了浓度增加的120 FN对MMP-1表达和成骨细胞标志物的影响。120 FN剂量依赖性地增加MMP-1的表达和活性，伴随着AP活性的降低。胶原酶活性的增加主要归因于MMP-1表达的增加。在AP活性降低的同时，120 FN降低了基线和地塞米松诱导的特异性成骨细胞标志物Runx 2和骨连接素的基因表达，并减少了矿化结节的形成。最后，siRNA抑制120 FN诱导的MMP-1减少胶原酶表达，并将AP表型挽救至基线水平。这些发现表明，疾病相关的120 FN，除了通过上调MMP对组织破坏有直接影响外，还可能通过阻碍成骨PDL细胞的成骨细胞分化促进疾病进展，从而减少骨再生。
Fibronectin (FN) fragments found in chronic inflammatory diseases, including periodontal disease and arthritis, may contribute to tissue destruction in part via induction of matrix metalloproteinases (MMPs). We previously showed that the 120-kDa FN fragment containing the central cell binding domain (120FN) dose dependently induces MMP-1 (collagenase-1) in human periodontal ligament (PDL) cells, whereas intact FN did not elicit this response. Recently, we found that an increase in MMP-1 expression is accompanied by a decreased osteoblastic phenotype in PDL cells. We hypothesized that 120FN inhibits osteoblastic differentiation of PDL cells by inducing MMP-1. Effects of increasing concentrations of 120FN on MMP-1 expression and on osteoblastic markers were assessed in cultured PDL cells using Western blotting, qRT-PCR, and collagen degradation and alkaline phosphatase (AP) activity assays. The 120FN dose dependently increased MMP-1 expression and activity, concomitant with a decrease in AP activity. The increase in collagenase activity was largely attributed to increased MMP-1 expression. Concurrent with the decrease in AP activity, the 120FN reduced baseline and dexamethasone-induced gene expression of specific osteoblastic markers, Runx2 and osteonectin, and diminished mineralized nodule formation. Finally, siRNA inhibition of 120FN-induced MMP-1 reduced collagenase expression and rescued the AP phenotype to baseline levels. These findings suggest that disease-associated 120FN, in addition to having direct effects on tissue destruction by upregulating MMPs, could contribute to disease progression by impeding osteoblastic differentiation of osteogenic PDL cells and, consequently, diminish bone regeneration.