Department of Conservative Dentistry and Periodontology, University Clinic of Dentistry, Medical University of Vienna, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria.
Austrian Cluster for Tissue Regeneration, Vienna, Austria; Department of Oral Surgery, University Clinic of Dentistry, Medical University of Vienna, Vienna, Austria.
J Endod. 2018 Aug;44(8):1263-1269. doi: 10.1016/j.joen.2018.04.010. Epub 2018 Jun 27.
Thixotropic synthetic clays have been successfully used for tissue engineering in regenerative medicine. The impact of these clays on the dental pulp, in particular in combination with hypoxia-based approaches using hypoxia mimetic agents (HMAs), is unknown. Our aim was to reveal the response of dental pulp-derived cells (DPCs) to a synthetic clay-based hydrogel and evaluate the release of HMAs.
Using resazurin-based toxicity assays, live-dead staining, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide staining, the viability of human DPCs seeded onto a synthetic clay-based hydrogel of 5%-0.15% as well as onto the hydrogels loaded with the HMAs dimethyloxalylglycine (DMOG), desferrioxamine, L-mimosine, and CoCl was evaluated. Furthermore, supernatant of the hydrogels loaded with HMAs were generated. Vascular endothelial growth factor (VEGF) production of DPCs in response to the supernatant was measured to reveal the cellular response to the HMAs.
We found that the synthetic clay-based hydrogel did not impair the viability of DPCs. Cell monolayer and cell cluster formations were observed on the hydrogel. No significant increase of VEGF levels was observed in the supernatant when DPCs were cultured on hydrogels loaded with HMAs. Supernatant of DMOG-loaded hydrogels stimulated VEGF production in DPCs in the first hour, whereas the effect of desferrioxamine, L-mimosine, and CoCl did not reach a level of significance.
The synthetic clay-based hydrogel represents a promising biomaterial that does not induce prominent toxic effects in DPCs. It can be loaded with DMOG to induce hypoxia mimetic activity. Overall, we provided first insights into the impact of synthetic clays on DPCs for tissue engineering purposes in regenerative endodontics.
触变合成粘土已成功用于再生医学中的组织工程。这些粘土对牙髓的影响，特别是与使用缺氧模拟剂（HMAs）的基于缺氧的方法结合使用时的影响尚不清楚。我们的目的是揭示牙髓来源的细胞（DPCs）对基于合成粘土的水凝胶的反应，并评估 HMA 的释放。
使用基于 Resazurin 的毒性测定、死活染色和 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐染色，评估人 DPCs 接种在 5%-0.15%的合成粘土基水凝胶以及负载 HMA 的水凝胶上的活力，这些 HMA 包括二甲氧酰基甘氨酸（DMOG）、去铁胺、L-刺桐碱和 CoCl。此外，还生成了负载 HMA 的水凝胶的上清液。测量 DPCs 对上清液的血管内皮生长因子（VEGF）产生，以揭示细胞对 HMA 的反应。
我们发现合成粘土基水凝胶不会损害 DPCs 的活力。在水凝胶上观察到细胞单层和细胞簇的形成。当 DPCs 培养在负载 HMA 的水凝胶上时，上清液中 VEGF 水平没有明显增加。DMOG 负载水凝胶的上清液在第一小时刺激 DPCs 产生 VEGF，而去铁胺、L-刺桐碱和 CoCl 的作用没有达到显著水平。
基于合成粘土的水凝胶是一种有前途的生物材料，不会在 DPCs 中引起明显的毒性作用。它可以负载 DMOG 以诱导缺氧模拟活性。总的来说，我们首次深入了解了合成粘土对牙髓细胞在再生牙髓学中的组织工程应用的影响。
