Vargas Fernanda da Silveira, Soares Diana Gabriela, Basso Fernanda Gonçalves, Hebling Josimeri, Costa Carlos Alberto de Souza
Department of Dental Materials and Prosthodontics, Araraquara School of Dentistry, Univ Estadual Paulista - UNESP, Araraquara, SP, Brazil.
Department of Physiology and Pathology, Araraquara School of Dentistry, Univ Estadual Paulista - UNESP, Araraquara, SP, Brazil.
Braz Dent J. 2014 Sep-Oct;25(5):367-71. doi: 10.1590/0103-6440201302434.
This in vitro study evaluated the potential protective effect of vitamin E alpha-tocopherol (α-T) isomer against the toxicity of hydrogen peroxide (HP) applied on dental pulp cells. Odontoblast-like MDPC-23 cells were seeded on 96-well plates for 72 h, treated with different concentrations of α-T (1, 3, 5, and 10 mM) for different times (1, 4, 8, and 24 h) and then exposed or not to a 0.018% HP solution for 30 min. In positive and negative control groups, cells were exposed to HP or culture medium (DMEM containing 5% DMSO), respectively. Cell viability was assessed by the MTT assay and the absorbance numeric data, expressed as percentage values, were subjected to the statistical analysis by Kruskal-Wallis and Mann-Whitney tests (α=5%). Considering the cells in the negative control as having 100% of cell viability, all combinations of α-T concentrations and pretreatment times showed a protective effect against HP cytotoxicity. Significant reduction of cell viability (59%) was observed in the positive control compared with the negative control. The highest values of pulp cell viability were obtained after pretreatment with 1 and 3 mM α-T concentrations for 24 h followed by exposure to HP (126% and 97% of cell viability, respectively). Under the tested conditions, the most effective cell protection against the cytotoxic effects of HP was provided by the lowest concentrations of α-T (1 and 3 mM) applied for 24 h.
这项体外研究评估了维生素Eα-生育酚（α-T）异构体对施加于牙髓细胞的过氧化氢（HP）毒性的潜在保护作用。将成牙本质细胞样MDPC-23细胞接种于96孔板中培养72小时，用不同浓度的α-T（1、3、5和10 mM）处理不同时间（1、4、8和24小时），然后暴露或不暴露于0.018%的HP溶液中30分钟。在阳性和阴性对照组中，细胞分别暴露于HP或培养基（含5%二甲基亚砜的DMEM）。通过MTT法评估细胞活力，将以百分比值表示的吸光度数值数据采用Kruskal-Wallis和Mann-Whitney检验进行统计分析（α = 5%）。以阴性对照组中的细胞具有100%的细胞活力为参照，α-T浓度和预处理时间的所有组合均显示出对HP细胞毒性的保护作用。与阴性对照组相比，阳性对照组中观察到细胞活力显著降低（59%）。在用1和3 mM α-T浓度预处理24小时后再暴露于HP后，获得了最高的牙髓细胞活力值（分别为细胞活力的126%和97%）。在测试条件下，对HP细胞毒性最有效的细胞保护作用是由应用24小时的最低浓度α-T（1和3 mM）提供的。
