Sato Ayako, Kajiya Hiroshi, Mori Nana, Sato Hironobu, Fukushima Tadao, Kido Hirofumi, Ohno Jun
Division of Oral Implantology, Department of Oral Rehabilitation, Fukuoka Dental College, Tamura, Sawara-ku, Fukuoka, Japan.
Research Center for Regenerative Medicine, Fukuoka Dental College, Tamura, Sawara-ku, Fukuoka, Japan.
PLoS One. 2017 Jan 6;12(1):e0169522. doi: 10.1371/journal.pone.0169522. eCollection 2017.
The initial step of bone regeneration requires the migration of osteogenic cells to defective sites. Our previous studies suggest that a salmon DNA-based scaffold can promote the bone regeneration of calvarial defects in rats. We speculate that the salmon DNA may possess osteoinductive properties, including the homing of migrating osteogenic cells. In the present study, we investigated the influence of the salmon DNA on osteoblastic differentiation and induction of osteoblast migration using MG63 cells (human preosteoblasts) in vitro. Moreover, we analyzed the bone regeneration of a critical-sized in vivo calvarial bone defect (CSD) model in rats. The salmon DNA enhanced both mRNA and protein expression of the osteogenesis-related factors, runt-related transcription factor 2 (Runx2), alkaline phosphatase, and osterix (OSX) in the MG63 cells, compared with the cultivation using osteogenic induction medium alone. From the histochemical and immunohistochemical assays using frozen sections of the bone defects from animals that were implanted with DNA disks, many cells were found to express aldehyde dehydrogenase 1, one of the markers for mesenchymal stem cells. In addition, OSX was observed in the replaced connective tissue of the bone defects. These findings indicate that the DNA induced the migration and accumulation of osteogenic cells to the regenerative tissue. Furthermore, an in vitro transwell migration assay showed that the addition of DNA enhanced an induction of osteoblast migration, compared with the medium alone. The implantation of the DNA disks promoted bone regeneration in the CSD of rats, compared with that of collagen disks. These results indicate that the salmon DNA enhanced osteoblastic differentiation and induction of migration, resulting in the facilitation of bone regeneration.
骨再生的初始步骤需要成骨细胞迁移至缺损部位。我们之前的研究表明，基于鲑鱼DNA的支架可促进大鼠颅骨缺损的骨再生。我们推测鲑鱼DNA可能具有骨诱导特性，包括引导迁移的成骨细胞归巢。在本研究中，我们在体外使用MG63细胞（人成骨前体细胞）研究了鲑鱼DNA对成骨细胞分化和诱导成骨细胞迁移的影响。此外，我们分析了大鼠体内临界大小颅骨骨缺损（CSD）模型的骨再生情况。与仅使用成骨诱导培养基培养相比，鲑鱼DNA增强了MG63细胞中成骨相关因子、 runt相关转录因子2（Runx2）、碱性磷酸酶和osterix（OSX）的mRNA和蛋白质表达。通过对植入DNA盘的动物骨缺损冰冻切片进行组织化学和免疫组织化学分析，发现许多细胞表达醛脱氢酶1，这是间充质干细胞的标志物之一。此外，在骨缺损的替代结缔组织中观察到了OSX。这些发现表明DNA诱导了成骨细胞向再生组织的迁移和聚集。此外，体外Transwell迁移试验表明，与单独的培养基相比，添加DNA增强了对成骨细胞迁移的诱导。与胶原盘相比，植入DNA盘促进了大鼠CSD的骨再生。这些结果表明，鲑鱼DNA增强了成骨细胞分化和迁移诱导，从而促进了骨再生。
