Department of Oral Implantology and Prosthodontics, Academic Centre For Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands.
Department of Oral Cell Biology, Academic Centre For Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands.
Int J Mol Sci. 2020 Jul 17;21(14):5072. doi: 10.3390/ijms21145072.
Osteoblasts derived from mouse skulls have increased osteoclastogenic potential compared to long bone osteoblasts when stimulated with 1,25(OH) vitamin D (vitD). This indicates that bone cells from specific sites can react differently to biochemical signals, e.g., during inflammation or as emitted by bioactive bone tissue-engineering constructs. Given the high turn-over of alveolar bone, we hypothesized that alveolar bone-derived osteoblasts have an increased osteogenic and osteoclastogenic potential compared to the osteoblasts derived from long bone. The osteogenic and osteoclastogenic capacity of alveolar bone cells and long bone cells were assessed in the presence and absence of osteotropic agent vitD. Both cell types were studied in osteogenesis experiments, using an osteogenic medium, and in osteoclastogenesis experiments by co-culturing osteoblasts with peripheral blood mononuclear cells (PBMCs). Both osteogenic and osteoclastic markers were measured. At day 0, long bones seem to have a more late-osteoblastic/preosteocyte-like phenotype compared to the alveolar bone cells as shown by slower proliferation, the higher expression of the matrix molecule ( and the osteocyte-enriched cytoskeletal component (. This phenotype was maintained during the osteogenesis assays, where long bone-derived cells still expressed more and . Under co-culture conditions with PBMCs, long bone cells also had a higher () expression and induced the formation of osteoclasts more than alveolar bone cells. Correspondingly, the expression of osteoclast genes () and was higher in long bone co-cultures. Together, our results indicate that long bone-derived osteoblasts are more active in bone-remodeling processes, especially in osteoclastogenesis, than alveolar bone-derived cells. This indicates that tissue-engineering solutions need to be specifically designed for the site of application, such as defects in long bones vs. the regeneration of alveolar bone after severe periodontitis.
与长骨成骨细胞相比，受 1,25(OH)维生素 D（vitD）刺激的鼠颅骨来源成骨细胞具有更高的破骨细胞生成潜力。这表明特定部位的骨细胞对生化信号的反应不同，例如在炎症期间或生物活性骨组织工程构建体发出的信号。考虑到牙槽骨的高周转率，我们假设与长骨来源的成骨细胞相比，牙槽骨来源的成骨细胞具有更高的成骨和破骨细胞生成潜力。在存在和不存在成骨活性药物 vitD 的情况下，评估了牙槽骨细胞和成骨细胞的成骨和破骨细胞能力。两种细胞类型均在成骨实验中使用成骨培养基进行研究，并在破骨细胞发生实验中通过与外周血单核细胞（PBMC）共培养进行研究。测量了两种成骨和破骨标志物。在第 0 天，与牙槽骨细胞相比，长骨似乎具有更晚期的成骨细胞/前成骨细胞样表型，这表现为增殖较慢、基质分子 () 的表达较高和富含骨细胞的细胞骨架成分 ()。这种表型在成骨实验中得以维持，其中长骨来源的细胞仍表达更高的 () 和 ()。在与 PBMC 共培养条件下，长骨细胞的 () 表达也更高，并比牙槽骨细胞诱导形成更多的破骨细胞。相应地，长骨共培养物中破骨细胞基因 () 和 () 的表达更高。总之，我们的结果表明，与牙槽骨来源的细胞相比，长骨来源的成骨细胞在骨重塑过程中更为活跃，尤其是在破骨细胞生成中。这表明组织工程解决方案需要针对应用部位进行专门设计，例如长骨缺陷与严重牙周炎后牙槽骨的再生。
